Infusion pump apparatus, method and system

ABSTRACT

A system is disclosed. The system includes a fill adapter device including a heat exchanger which includes a heating element and a fluid pathway, the fluid pathway fluidly connected to a filling needle input, whereby fluid enters the heat exchanger through the filling needle input and flows through the fluid pathway and whereby the fluid is heated by the heating element. The system also includes a reservoir including a plunger and a plunger rod and a filling needle configured to be removably attached to the reservoir, wherein the fill adapter is configured to be attached to a vial of fluid and wherein fluid from the vial flows through the fluid pathway and is heated and loaded into the reservoir through the filling needle.

CROSS REFERENCE TO RELATED APPLICATION(S)

The present application is a Non-Provisional Application which claimspriority from U.S. Provisional Patent Application Ser. No. 61/301,957,filed Feb. 5, 2010 and entitled Infusion Pump Apparatus, Method andSystem, which is hereby incorporated herein by reference in itsentirety.

TECHNICAL FIELD

The present disclosure relates to medical devices and more particularly,to an infusion pump apparatus, methods and systems.

BACKGROUND INFORMATION

Many potentially valuable medicines or compounds, including biologicals,are not orally active due to poor absorption, hepatic metabolism orother pharmacokinetic factors. Additionally, some therapeutic compounds,although they can be orally absorbed, are sometimes required to beadministered so often it is difficult for a patient to maintain thedesired schedule. In these cases, parenteral delivery is often employedor could be employed.

Effective parenteral routes of drug delivery, as well as other fluidsand compounds, such as subcutaneous injection, intramuscular injection,and intravenous (IV) administration include puncture of the skin with aneedle or stylet. Insulin is an example of a therapeutic fluid that isself-injected by millions of diabetic patients. Users of parenterallydelivered drugs may benefit from a wearable device that wouldautomatically deliver needed drugs/compounds over a period of time.

To this end, there have been efforts to design portable and wearabledevices for the controlled release of therapeutics. Such devices areknown to have a reservoir such as a cartridge, syringe, or bag, and tobe electronically controlled. These devices suffer from a number ofdrawbacks including the malfunction rate. Reducing the size, weight andcost of these devices is also an ongoing challenge. Additionally, thesedevices often apply to the skin and pose the challenge of frequentre-location for application.

SUMMARY

In accordance with one aspect of the present invention, a system isdisclosed. The system includes a fill adapter device including a heatexchanger which includes a heating element and a fluid pathway, thefluid pathway fluidly connected to a filling needle input, whereby fluidenters the heat exchanger through the filling needle input and flowsthrough the fluid pathway and whereby the fluid is heated by the heatingelement. The system also includes a reservoir including a plunger and aplunger rod and a filling needle configured to be removably attached tothe reservoir, wherein the fill adapter is configured to be attached toa vial of fluid and wherein fluid from the vial flows through the fluidpathway and is heated and loaded into the reservoir through the fillingneedle.

Some embodiments of this aspect of the invention may include one or moreof the following. Wherein the system further includes a pump to pumpfluid into the fluid pathway at a predetermined rate. Wherein the systemfurther includes a check valve for metering fluid into the fluid pathwaywhereby the rate of flow of fluid through the heat exchanger iscontroller. Wherein the system further includes a processor forcontrolling the heating of the fluid according to one or morepreprogrammed profiles. Wherein the system further includes wherein thefilling needle input is a septum. Wherein the system further includes anair trap whereby the air trap allows air to flow out of the heatexchanger. Wherein the system further includes wherein the air trapcomprising a hydrophobic filter.

In accordance with one aspect of the present invention, a fill adapterdevice is disclosed. The fill adapter device includes a heat exchangerincluding a heating element and a fluid pathway, the fluid pathwayfluidly connected to a filling needle input and a vial, whereby fluidfrom the vial enters the heat exchanger and flows through the fluidpathway and whereby the fluid is heated by the heating element.

Some embodiments of this aspect of the invention may include one or moreof the following. Wherein the device further includes a pump to pumpfluid into the fluid pathway at a predetermined rate. Wherein the devicefurther includes a check valve for metering fluid into the fluid pathwaywhereby the rate of flow of fluid through the heat exchanger iscontroller. Wherein the device further includes a processor forcontrolling the heating of the fluid according to one or morepreprogrammed profiles. Wherein the device further includes wherein thefill adapter is configured to be attached to a vial of fluid. Whereinthe device further includes wherein the filling needle input is aseptum. Wherein the device further includes an air trap whereby the airtrap allows air to flow out of the heat exchanger. Wherein the devicefurther includes wherein the air trap comprising a hydrophobic filter.

In accordance with one aspect of the present invention, a method foratmospheric mitigation in an infusion pump is disclosed. The methodincludes a pressure sensor sending data to a pump processor at apredetermined interval, determining if the data exceeds an alarmthreshold, if the data exceeds a predetermined alarm threshold, theprocessor indicating to the user to disconnect from a cannula,determining if the data meets a pre-determined safe threshold, andindicating to the user to re-connect to the cannula.

In accordance with one aspect of the present invention, an infusion pumpsystem is disclosed. The system includes a reservoir, an active checkvalve located downstream from the reservoir and upstream from a cannula,a passive check valve having a cracking pressure located downstream fromthe reservoir, and a pump processor, wherein the active check valve isopened by the pump processor for scheduled pump deliveries, wherein whenfluid pressure overcomes the cracking pressure, the passive check valveopens, and fluid flows from the reservoir and through the passive checkvalve.

In accordance with one aspect of the present invention, an infusion pumpsystem is disclosed. The system includes a reservoir and at least onevalve downstream from the reservoir wherein at least one valve is apressure compensation valve having a cracking pressure wherein adifferential pressure related to the change a altitude of the infusionpump cases the at least one valve to open.

In accordance with one aspect of the present invention, a method foratmospheric mitigation in an infusion pump is disclosed. The methodincludes receiving information related to a scheduled departure and ascheduled landing time, modifying the frequency of processing datarelated to altitude based on the information, determining, by comparingthe information and the altimeter, whether a change in schedule may beoccurring, alerting a user of a change of schedule, requesting updatedschedule information, and modifying the scheduled delivery of fluidbased on the entered schedule a altimeter data.

In accordance with one aspect of the present invention, an infusion pumpsystem is disclosed. The system includes a reservoir comprising aplunger, at least one sensor for determining the location of theplunger, and a processor configured to receive information from the atleast one sensor. The processor is configured to modify the frequency ofdetermination of the location of the plunger and the processor isconfigured to determine the volume of fluid either siphoned into ordelivered out of a reservoir and modify scheduled pump deliveries for apredetermined amount of time.

In accordance with one aspect of the present invention, a system fortemperature compensation for an infusion pump is disclosed. The systemincludes at least one temperature sensor and at least one processor, theprocessor in communication with the temperature sensor, wherein theprocessor determines a target plunger position and, based at least uponcommunication from the temperature sensor, modifies the target plungerposition based on the temperature sensed.

In accordance with one aspect of the present invention, a system forpressure mitigation for an infusion pump is disclosed. The systemincludes at least one pressure sensor; and a processor, wherein thepressure sensor sends data to the processor and the processor mitigatespressure changes if the pressure changes meet a preprogrammed threshold.

These aspects of the invention are not meant to be exclusive and otherfeatures, aspects, and advantages of the present invention will bereadily apparent to those of ordinary skill in the art when read inconjunction with the appended claims and accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features and advantages of the present invention will bebetter understood by reading the following detailed description, takentogether with the drawings wherein:

FIGS. 1A-1B are front and back isometric view of an embodiment of aninfusion pump;

FIGS. 1C-1E are side and front views of the infusion pump assembly ofFIG. 1;

FIG. 1F is a front isometric view of the infusion pump assembly of FIG.1;

FIG. 2 is an illustrative view of one embodiment of a remote controlassembly;

FIG. 3 is a diagrammatic view of the infusion pump assembly of FIG. 1;

FIGS. 4A-4E depict a plurality of hook-and-loop fastener configurationsaccording to some embodiments;

FIG. 5 is an illustration of one embodiment of a holder;

FIG. 6 is an illustration of one embodiment of a user wearing a holder;

FIG. 7 is an illustration of one embodiment of the back of a holder;

FIG. 8 is an illustration of one embodiment of a vial with a temperaturegauge/label:

FIG. 9 is a flowchart of one embodiment of method for atmosphericpressure determination and mitigation;

FIG. 10 is an illustration of one embodiment of a passive and activecheck valve embodiment;

FIG. 11 is an illustration of a cross sectional view of one embodimentof a fill adapter;

FIG. 12 is an illustration of a vial system for maintaining a vacuumwithin a vial according to one embodiment;

FIG. 13 is an illustration of a vial apparatus according to oneembodiment; and

Appendix A is one embodiment of a micro check valve used in someembodiments.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS Definitions

As used in this description and the accompanying claims, the followingterms shall have the meanings indicated, unless the context otherwiserequires:

A “device” shall mean a medical device, which includes, but is notlimited to, an infusion pump and/or a controller, i.e., a device forwireless control of another medical device. In some embodiments, theword “device” is used interchangeably with “pump”, “infusion pump”and/or “controller” and/or “Companion” and/or “remote controller device”and/or “remote controller assembly”.

A “Companion” shall mean a device for wireless control of anothermedical device. In the exemplary embodiments, the Companion may alsoinclude a glucose meter/strip reader.

An “input” of a device includes any mechanism by which a user of thedevice or other operator/caregiver may control a function of the device.User inputs may include mechanical arrangements (e.g., switches,pushbuttons, jogwheel(s)), electrical arrangements (e.g., a slider,touch screen), wireless interfaces for communication with a remotecontroller (e.g., RF, infrared), acoustic interfaces (e.g., with speechrecognition), computer network interfaces (e.g., USB port), and othertypes of interfaces.

A “button” in the context of an input such as the so-called “bolusbutton” discussed below may be any type of user input capable ofperforming a desired function, and is not limited to a pushbutton, aslider, switch, touch screen or a jog wheel.

An “alarm” includes any mechanism by which an alert may be generated toa user or third party. Alarms may include audible alarms (e.g., aspeaker, a buzzer, a speech generator), visual alarms (e.g., an LED, anLCD screen), tactile alarms (e.g., a vibrating element), wirelesssignals (e.g., a wireless transmission to a remote controller orcaretaker), or other mechanism. Alarms may be generated using multiplemechanisms simultaneously, concurrently, or in a sequence, includingredundant mechanisms (e.g., two different audio alarms) or complementarymechanisms (e.g., an audio alarm, a tactile alarm, and a wirelessalarm).

“Fluid” shall mean a substance, a liquid for example, that is capable offlowing through a flow line.

A “user” includes a person or animal who receives fluid from a fluiddelivery device, whether as part of a medical treatment or otherwise, ora caregiver or third party involved in programming the device orotherwise interacting with the device to infuse fluid to another.

“Cannula” shall mean a disposable device capable of infusing fluid to auser. A cannula as used herein may refer to a traditional cannula or toa needle.

“Disposable” refers to a part, device, portion or other that is intendedto be used for a fixed duration of time, then discarded and replaced.

“Reusable” refers to a portion that is intended to have an open-endedduration of use.

“Acoustic volume measurement” shall mean quantitative measurement of arelevant volume using acoustical techniques such as those described inU.S. Pat. Nos. 5,349,852 and 5,641,892, which are hereby incorporated byreference herein in their entireties, as well as other techniques.

A “temperature sensor” includes any temperature determinationdevice/mechanism for measuring temperature and communicating temperatureinformation to a controller and/or to a pump processor. The devicesdescribed herein may include one or more temperature sensors formeasuring such things as including, but not limited to, one or more ofthe following: user skin temperature, AVS temperature, ambienttemperature, internal pump temperature, plunger temperature, drive traintemperature and fluid temperatures.

An exemplary use of embodiments of the devices, methods and systemsdescribed here is for the delivery of insulin to people living withdiabetes, but other uses include delivery of any fluid, as describedabove. Fluids include analgesics to those in pain, chemotherapy tocancer patients and enzymes to patients with metabolic disorders.Various therapeutic fluids may include small molecules, naturalproducts, peptide, proteins, nucleic acids, carbohydrates,nanoparticulate suspensions, and associated pharmaceutically acceptablecarrier molecules. Therapeutically active molecules may be modified toimprove stability in the device (e.g., by pegylation of peptides orproteins). Although illustrative embodiments herein describedrug-delivery applications, embodiments may be used for otherapplications including liquid dispensing of reagents for high throughputanalytical measurements such as lab-on-chip applications and capillarychromatography. For purposes of description below, terms “therapeutic”,“insulin” or “fluid” are used interchangeably, however, in otherembodiments, any fluid, as described above, may be used. Thus, thedevice and description included herein are not limited to use withtherapeutics.

Some embodiments of the fluid delivery device are adapted for use bypeople living with diabetes and/or their caregivers. Thus, in theseembodiments, the devices, methods and systems work to delivers insulinwhich supplements or replaces the action of the person living withdiabetes' (referred to as the user) pancreatic islet beta cells.Embodiments adapted for insulin delivery seek to mimic the action of thepancreas by providing both a basal level of fluid delivery as well asbolus levels of delivery. Basal levels, bolus levels and timing may beset by the user or a caregiver by using a wireless handheld userinterface or directly by using a pump. Additionally, basal and/or boluslevels may be triggered or adjusted in response to the output of aglucose meter, which in the exemplary embodiments, is integral to thecontroller. In other embodiments, the controller additionally includes aglucose monitoring device which receives data from a blood glucosesensor. In some embodiments, a bolus may be triggered by a user using adesignated button or other input means located on a device, i.e., on thecontroller and/or on an infusion pump. In still other embodiments, thebolus or basal may be programmed or administered through a userinterface located either on the fluid delivery device/infusion pumpand/or on the controller.

With respect to the names given to screens and types of screens, as wellas proper names given to various features, throughout variousembodiments, these terms may vary.

The systems and methods described herein may be used to control aninfusion pump. For purposes of this description, the various embodimentsof the user interface and the infusion pump may be described withreference to an insulin pump, or a pump which infuses insulin. However,it should be understood that the user interface may be on an infusionpump and/or on a controller. Additionally, where the descriptionpertains to an infusion pump “screen”, this “screen” may also appear ona controller, or may appear on a controller in lieu of a pump.

Infusion pumps contemplated by this description include a pump which maypump any fluid, including, but not limited to, a therapeutic fluid,which includes, but is not limited to, insulin. Thus, where thisdescription describes the exemplary embodiment as pertaining to insulin,this is meant merely for descriptive purpose only as the device is notintended to be limited to insulin. Other fluids are also contemplated.In some embodiments, the methods, systems and devices described hereinmay be used in conjunction with insulin “pens” and/or fluid delivery“pens”, which are known in the art.

The infusion pump may be any infusion pump, for example, but not limitedto, the pump devices shown and described with respect to FIGS. 1A-1F andthose incorporated herein by reference, and include, but are not limitedto, those incorporated herein by reference. In the various exemplaryembodiments, the infusion pump is a syringe-pump, i.e., the fluid ispumped or delivered to the user when a plunger advances in a syringe,pushing the fluid inside the syringe into a cannula. Where the cannulais connected to a user (i.e., the cannula is within the user'ssubcutaneous region) the fluid is delivered subcutaneously to the user.

In the exemplary embodiment, the infusion pump includes hardware forwireless RF communication with a controller. However, in variousembodiments, the infusion pump may be any infusion pump. Referring toFIGS. 1A-1F and, in some exemplary embodiments, the infusion pump mayinclude a display assembly 104, however, in other exemplary embodiments,such as those shown in FIGS., the infusion pump may not include adisplay assembly. In these embodiments, a display assembly which may besimilar to the one shown in FIGS. 1A, 1D and 1F, or may be larger orsmaller, is included on a controller or companion device. An embodimentof the controller or companion device is shown in FIG. 2.

Referring to FIGS. 1A-1F, an embodiment of an infusion pump assembly 100that may be housed within enclosure assembly 102 is shown. Infusion pumpassembly 100 may include a display system 104 that may be visiblethrough the enclosure assembly 102. One or more switch assemblies/inputdevices 106, 108, 110 may be positioned about various portions of theenclosure assembly 102. The enclosure assembly 102 may include infusionport assembly 112 to which cannula assembly 114 may be releasablycoupled. A removable cover assembly 116 may allow access to a powersupply cavity 118 (shown in phantom on FIG. 1D).

Referring to the infusion pump assemblies shown in FIG. 1A-1F, infusionpump assembly 100 may include processing logic (not shown), which may bereferred to as the pump processor, that executes one or more processesthat may be required for infusion pump assembly 100 to operate properly.Processing logic may include one or more microprocessors (not shown),one or more input/output controllers (not shown), and cache memorydevices (not shown). One or more data buses and/or memory buses may beused to interconnect processing logic with one or more subsystems. Insome embodiments, at least one of the subsystems shown in FIG. 3 is alsoincluded in the embodiment of the infusion pump assembly 100 shown inFIGS. 1A-1F.

Referring now to FIGS. 1A-1F and FIG. 3, examples of the subsystemsinterconnected with processing logic 400 may include but are not limitedto memory system 402, input system 404, display system 406, vibrationsystem 408, audio system 410 motor assembly 416, force sensor 412.temperature sensor (not shown) and displacement detection device 418(which may be referred to as a device to determine and/or detect thedistance the plunger has moved with respect to the syringebarrel/syringe). Infusion pump assembly 100 may include primary powersupply 420 (e.g. a battery) configured to be removable installablewithin power supply cavity 118 and to provide electrical power to atleast a portion of processing logic 400 and one or more of thesubsystems (e.g., memory system 402, input system 404, display system406, vibration system 408, audio system 410, motor assembly 416, forcesensor 412, and displacement detection device 418).

Infusion pump assembly 100 may include reservoir assembly 430 configuredto contain infusible fluid 422. In some embodiments, reservoir assembly430 may be a reservoir assembly similar to that described in U.S. Pat.No. 7,498,563, issued Mar. 3, 2009 and entitled Optical DisplacementSensor for Infusion Devices, which is herein incorporated by referencein its entirety, and/or as described in U.S. Pat. No. 7,306,578, issuedDec. 11, 2007 and entitled Loading Mechanism for Infusion Pump; PCTApplication Serial No. PCT/US2009/060158, filed Oct. 9, 2009 andentitled Infusion Pump Assembly, now Publication No. WO 2010/042814,published Apr. 15, 2010; and U.S. patent application Ser. No.12/249,882, filed Oct. 10, 2008 and entitled Infusion Pump Assembly, nowU.S. Publication No. US-2010-0094222, published Apr. 15, 2010, all ofwhich are hereby incorporated herein in their entireties. In otherembodiments, the reservoir assembly may be any assembly in which fluidmay be acted upon such that at least a portion of the fluid may flow outof the reservoir assembly, for example, the reservoir assembly, invarious embodiments, may include but is not limited to: a barrel with aplunger, a barrel with a plunger connected to a plunger rod, a cassetteand/or a container at least partially constructed of a flexiblemembrane.

Plunger assembly 424 may be configured to displace infusible fluid 422from reservoir assembly 430 through cannula assembly 450 (which may becoupled to infusion pump assembly 100 via infusion port assembly 424) sothat infusible fluid 422 may be delivered to user 454. In thisparticular embodiment, plunger assembly 424 is shown to be displaceableby partial nut assembly 426, which may engage lead screw assembly 428that may be rotatable by motor assembly 416 in response to signalsreceived from processing logic 400. In this particular embodiment, thecombination of motor assembly 416, plunger assembly 424, partial nutassembly 426, and lead screw assembly 428 may form a pump assembly thateffectuates the dispensing of infusible fluid 422 contained withinreservoir assembly 430. An example of partial nut assembly 426 mayinclude but is not limited to a nut assembly that is configured to wraparound lead screw assembly 426 by e.g., 30 degrees. In some embodiments,the pump assembly may be similar to one described in U.S. Pat. No.7,306,578, issued Dec. 11, 2007 and entitled Loading Mechanism forInfusion Pump; U.S. patent application Ser. No. 12/249,882, filed Oct.10, 2008 and entitled Infusion Pump Assembly, now U.S. Publication No.US-2010-0094222, published Apr. 15, 2010; and U.S. patent applicationSer. No. 12/249,891, filed Oct. 10, 2008 and entitled Infusion PumpAssembly, now U.S. Publication No. US-2009-0099523 published Apr. 16,2009, all of which are herein incorporated by reference in theirentireties.

User Interface

Throughout this description, screens may be referenced with respect tothe “pump” or “Companion” or “Controller”. However, in variousembodiments, a similar screen or a similar method may be accomplished onanother device. For example, where the screen or method is referencedwith respect to the “pump”, a similarly functional screen or method maybe used on the “Companion” or “Controller” in other embodiments. As thisdescription includes embodiments related to both pumps having displaysand pumps having no displays, it should be evident that where theembodiment includes an infusion pump without a display, any screens willbe visible on a Companion or Controller. Similarly, where a methodrequires an interaction between the user and the pump, the interactionmay be accomplished via a switch assembly on the pump where the pump isan infusion pump without a display.

Processing logic which in some embodiments, includes at least oneelement as shown in described with respect to FIG. 3, is used to receiveinputs from a user or caregiver. The user or caregiver uses one or moreinput devices or assemblies, including but not limited to, one or moreof the following: button/switch assembly, slider assemblies, including,but not limited to, capacitive sliders (which may include, for example,including but not limited to any slider described in U.S. patentapplication Ser. No. 11/999,268, filed Dec. 4, 2007 and entitled MedicalDevice Including a Slider Assembly, now U.S. Publication No.US-2008-0177900, published Jul. 24, 2008, which is hereby incorporatedherein by reference in its entirety, jog wheel and/or touch screen. Theinfusion device additionally received inputs from internal systems,including but not limited to occlusion detection process 438,confirmation process 440, volume measurement technology (e.g., acousticvolume sensing). Using these inputs, the infusion device producesoutputs, for example including, but not limited to, infusion fluiddelivery to the user or comments, alerts, alarms or warnings to theuser. The inputs are thus either directly from the user to the pump,directly from the pump systems to the processing logic, or from anotherdevice, e.g., a remote controller device (described in more detailbelow), to the pump. The user or caregiver interaction experience thusincludes, but is not limited to, one or more of the following:interaction with a display (either on the infusion pump device itself ora remote controller device or both), which includes but is not limitedto, reading/seeing text and/or graphics on a display, direct interactionwith a display, for example, through a touch screen, interaction withone or more buttons, sliders, jog wheels, one or more glucose stripreaders, and sensing either through touch sensation or audio, one ormore vibration motors, and/or an audio system. Thus, the term “userinterface” is used to encompass all of the systems and methods a user orcaregiver interacts with the infusion pump, to control the infusionpump.

Referring now to FIG. 2, in some embodiments of the infusion pumpsystem, the infusion pump may be remotely controlled using a remotecontroller assembly 300, also referred to as a controller or acompanion. Remote control assembly 300 may include all, or a portion of,the functionality of the infusion pump assembly shown in FIGS. 1A-1F,itself. Thus, in some exemplary embodiments of the above-describedinfusion pump assembly, the infusion pump assembly (not shown, see FIGS.1A-1F, amongst other FIGS.) may be configured via remote controlassembly 300. In these particular embodiments, the infusion pumpassembly may include telemetry circuitry (not shown) that allows forcommunication (e.g., wired or wireless) between the infusion pumpassembly and e.g., remote control assembly 300, thus allowing remotecontrol assembly 300 to remotely control infusion pump assembly 100.Remote control assembly 300 (which may also include telemetry circuitry(not shown) and may be capable of communicating with infusion pumpassembly) may include display assembly 302 and an input assembly, whichmay include one or more of the following: an input control device (suchas jog wheel 306, slider assembly 310, or another conventional mode forinput into a device), and switch assemblies 304, 308. Thus, althoughremote control assembly 300 as shown in FIG. 2 includes jog wheel 306and slider assembly 310, some embodiments may include only one of eitherjog wheel 306 or slider assembly 310, or another conventional mode forinput into a device. In embodiments having jog wheel 306, jog wheel 306may include a wheel, ring, knob, or the like, that may be coupled to arotary encoder, or other rotary transducer, for providing a controlsignal based upon, at least in part, movement of the wheel, ring, knob,or the like.

Remote control assembly 300 may include the ability to pre-program basalrates, bolus alarms, delivery limitations, and allow the user to viewhistory and to establish user preferences. Remote control assembly 300may also include a glucose strip reader 312.

During use, remote control assembly 300 may provide instructions to theinfusion pump assembly via a wireless communication channel establishedbetween remote control assembly 300 and the infusion pump assembly.Accordingly, the user may use remote control assembly 300 toprogram/configure the infusion pump assembly. Some or all of thecommunication between remote control assembly 300 and the infusion pumpassembly may be encrypted to provide an enhanced level of security.

In the exemplary embodiments of the user interface, the user interfacemay require user confirmation and user input. The exemplary embodimentsof the user interface are centered on ensuring the user knows the effectof various interactions on the pump. Many examples will be presentedthroughout this description of the pump communicating the result of theuser's actions to the user. These features ensure the user understandstheir actions and therefore, imparts greater safety onto the user. Onesuch example is throughout the exemplary embodiment of the userinterface, where the user presses the back button on a screen after avalue has been changed, the user interface displays the Cancel Changesconfirmation screen. If the user selects “Yes”, the user interfacediscards any pending changes, closes the confirmation screen and goesback to the previous screen (i.e., the screen previous to the screenwhere the user pressed the Back button). When the action selection is“No”, on the “Cancel Changes?” confirmation screen, the user presses theenter button or other depending on the embodiment, and the userinterface closes the confirmation screen and returns to the screen withpending changes. This feature prevents the outcome where the userassumes the changes have been implemented, but in fact, they have notbeen. Thus, this feature prevents that circumstance and ensures the userunderstands that the changes have not been implemented.

Temperature

In various embodiments of the infusion pump, the user may wear theinfusion pump either attached to a belt, attached to another article orclothing or a garment such that the device is worn on the body, or, insome embodiments, attached to an undergarment, in a pocket or, in someembodiments, attached to the skin of the user. The user generally wearsthe infusion pump as close to twenty-four (24) hours a day as possible,and in some cases, removing the device for short periods of time, forexample, but not limited to, during an MRI or other treatment that mayeffect the device and/or while showering/bathing. Thus, during thenormal course of the user's wearing the infusion pump, the infusion pumpmay be exposed to various temperatures, including, temperature swings,which may include positive temperature swings and/or negativetemperature swings. These temperature swings may be the result of theuser stepping out of doors, into a cold room, into a hot room and/orunder a blanket or other warming agent.

The fluid contained in the reservoir while in the pump, which, asdiscussed above, may include, but is not limited to insulin, has athermal expansion coefficient which may be referred to as a generalvolumetric thermal expansion coefficient. Thus, during a temperatureswing/differential/change, whether positive or negative, the fluid, orinsulin, will expand or contract. Various factors may contribute to theexpansion or contraction of the fluid including but not limited to therate of change of the temperature. Thus, in some embodiments, the amountof expansion or contraction may be a function of the temperature.

Additionally, in various embodiments of the various embodiments of thedevices described the components of the pumps also have thermalexpansion coefficients. These thermal expansion coefficients may varydepending on the material. Thus, where the various components are madefrom different materials, the thermal expansion coefficients may vary.

In some embodiments, a change in temperature may affect a thermalexpansion or thermal contraction of the fluid and/or one or morecomponents of the infusion pump. For example, but not limited to, anincrease in temperature may cause an increase in the diameter of thereservoir/syringe 430 (for illustration only, please refer to FIG. 3).This may be because the relative thermal expansion of the syringecompared with the fluid governs whether fluid is delivered or pulledback. Thus, this in turn may cause any fluid/insulin in the cannula 450to flow backwards, towards the reservoir 430. In this case, a volume offluid/insulin is pulled back into the reservoir. Thus, a subsequentrequest for a delivery by processing logic 400 may only result in thisretracted volume being delivered to the user. Thus, a volume offluid/insulin (the retracted volume) has not been delivered to the userwithout request or knowledge by the user. Another example includestemperature decrease. In some embodiments, a temperature decrease maycause the reservoir 430 to decrease in diameter, causing fluid/insulinto flow to the cannula 450. Thus, an unintended bolus volume isdelivered to this user. In this case, fluid/insulin has been deliveredto the user without request or knowledge by the user.

Thus, in the first example, the user may receive less fluid/insulin thanis required or requested and thus, may experience hyperglycemia. In thesecond example, the user may receive more fluid/insulin than is requiredor requested and thus, may experience hypoglycemia. In either example,the user receives a fluid/insulin volume that is not the same as therequested or programmed therapy and is not notified of the disparity.

In these examples, the reservoir is assumed to be a cylinder. Below is amathematical model of the change in volume of a cylinder (assuming aconstant coefficient of linear expansion, α). This is a model forexplanation purposes. Additional mathematical models may be determinedto accommodate additional assumptions, for example, a shape other than acylinder, or a syringe with a movable plunger.ΔV=V(3αΔT+3α² ΔT ²+α³ ΔT ³)  [EQ#1]

-   -   Which may be simplified assuming αΔT<<1 to:

$\begin{matrix}{\frac{\Delta\; V}{V} \approx {3{\alpha\Delta}\; T}} & \left. {{EQ}\#\; 2} \right\rbrack\end{matrix}$

-   -   Thus, the volume change of a cylinder made from polypropylene        where the temperature changes from 30 C to 10 C for        polypropylene, which is a material with linear coefficient of        linear expansion

${\alpha = {86 \times 10^{- 6}\mspace{14mu}\frac{cm}{{cm} \cdot K}}},$would be:

$\begin{matrix}{{\frac{\Delta\; V}{V} \approx {3\left( {86 \times 10^{- 6}\mspace{14mu}\frac{cm}{{cm} \cdot K}} \right)\left( {20\; K} \right)}} = {0.52\%}} & \left. {{EQ}{\# 3}} \right\rbrack\end{matrix}$

The change in specific volume for water between 30 C and 10 C is about0.40%. The difference between the two (about 0.12%) applied to a 3 ccsyringe or reservoir would be about 3.6 μL. However, in addition, thesyringe plunger may move in response to the thermal expansion dependingon the plunger material and the relationship of the syringe in the pump(e.g., the design of the syringe retention in the pump).

Therefore, there may be a desire to minimize the effect of temperatureon the delivery of fluid. Thus, it may be desired to limit or minimize,and/or characterize, the thermal expansion of the fluid and/or one ormore of the components of the infusion pump. The systems, methods andapparatus described to minimize the effect of temperature on the thermalexpansion of the fluid and/or one of more of the components of theinfusion pump may include one or more of the following exemplaryembodiments.

In some embodiments, selection of materials with predictable andfavorable thermal expansion coefficients may minimize the potentialunder and over delivery of fluids as discussed above. In someembodiments, the syringe material, for example, may be selected to matchthe thermal expansion of the fluid. For example, the linear expansioncoefficient for water at about 20 C is about:

$\begin{matrix}{68.9 \times 10^{- 6}\mspace{14mu}\frac{cm}{{cm} \cdot K}} & \left. {{EQ}{\# 4}} \right\rbrack\end{matrix}$

Thus, the syringe material may be selected to have an expansioncoefficient close to this value. For example, a blend of polycarbonateand acrylonitrile butadiene styrene (also referred to as “ABS”) could beused to match the thermal expansion coefficient of the fluid. In someembodiments, other plastics, for example, but not limited to,polycarbonate, may be close to the correct expansion coefficient suchthat the volume delivered by the syringe pump due to the expectedtemperature change is minimal and/or acceptable. In some embodiments,the plastic or material selected may be tailored to the slope of thethermal expansion of the fluid.

In some embodiments, the material of the plunger and/or the plunger rodmay be selected to thermally differentially compensate for the change intemperature. In some embodiments, the materials for the syringe, plungerand plunger rod may be selected to thermally differentially compensatefor the change in temperature. Also, or in addition to, in someembodiments, the material of one or more components of the drive train,or any other component of the infusion pump, may be selected tothermally differentially compensate for the change in temperature.

In some embodiments, the materials for any one or more infusion pumpcomponents may be selected to have an opposite thermal coefficient, or athermally compensating material to minimize the thermal expansioneffects of the temperature. For example, in higher temperatures, wherethe infusion pumps syringe expands, the flow of fluid may be negative.In some embodiments, at least one component of the drive train may havea negative thermal constant, thus, having the opposite thermalcoefficient. Thus, upon a temperature increase, the syringe does notexperience a change in volume.

In some embodiments, the use of a material which may undergo a phasechange during a temperature change event may minimize the effect of thetemperature differential/change on the infusion pump. For example, insome embodiments, the plunger may include a predetermined volume of wax,thus, as the temperature increases, the length or position may increasedue to the phase change of the wax. Additional wax features may be addedin some embodiments to prevent flow. In some embodiments, a wax featuremay be added to move the plunger forward a (predetermined) distance suchthat the resulting change in the volume is equal to the square root ofthe diameter of the plunger. Thus, in some embodiments, the use of amaterial which undergoes a phase change in response totemperature/temperature change/differential may be used to compensatefor the change of volume of the syringe due to a temperature change. Insome embodiments, the material which undergoes a phase change inresponse to a temperature change may absorb the energy of the thermaldifferential, thus, for example, where the temperature is increasing,rather than rising the temperature of the infusion pump, the wax, orother phase change material, may melt the wax/phase change material,thus, acting as an energy sink and absorbing the heat.

In some embodiments, the syringe may be constrained in such a way that achange in temperature may cause the plunger to be advanced or withdrawnto compensate for the volume change of the syringe. For example, in someembodiments, the syringe may be held in a metal case, the metals thatmay be used include but are not limited to, steel, aluminum, and/or anymetal with a low coefficient of thermal expansion, which may include,but is not limited to, FeNi36, also known as INVAR®. The plunger may bemade from a material that has a high coefficient of thermal expansion.Thus, in this example, a decrease in temperature may cause the syringeplunger to be withdrawn as the diameter of the syringe barrel isdecreasing. Thus, balancing these effects, the change in the totalvolume may be minimized.

Characterization and Controls Compensation

In some embodiments, characterizing the effect of a change intemperature on the volume of fluid pumped by the infusion device may becompleted. In this embodiment, the pump may be subjected to temperaturevariation (i.e., both positive and negative) and the correspondingresponse by the infusion pump may be recorded. The characterization mayinclude, but is not limited to, varying rates of change (i.e., 1 degreeCelsius per minute, and whether positive and negative, etc), totaltemperature variation (e.g., 10 degrees Celsius, 5 degrees Celsius,etc), and/or position of syringe plunger.

The infusion pump may include one or more devices and/or componentsand/or systems to determine the temperature. In some embodiments, theinfusion pump may include one or more thermistors or other temperaturesensors to determine the temperature. However, in other embodiments,various methods and/or devices and/or systems to determine thetemperature, either directly or indirectly, may be used, including, butnot limited to, one or more of the following: at least one resistancetemperature device (RTD) and/or at least one non-contact infrared device(non-contact IR). The location of the one or more thermistors and/ortemperature determination devices may vary. The locations of one of moreof the thermistors and/or temperature determination devices may include,but is not limited to, the drive screw, any location on the drive train,on the syringe barrel, including but not limited to, printed on thesyringe barrel, the plunger and/or, the printed circuit board. Invarious embodiments, the one or more thermistor(s) and/or temperaturedetermination devices location may be any where away from the heatsources that would render a potentially false reading. In someembodiments, the one or more thermistors may determine the temperatureof one or more locations, including, but not limited to, inside of thesyringe, the outside of the syringe, the inside of the pump, and/or theoutside of the pump. Various controls may be determined based on atemperature model in any one or more of these locations. Thus, in someembodiments, the characterization may be made by taking temperaturereadings both within the syringe and outside of the syringe. In otherembodiments, the characterization may be performed by taking temperaturereadings from outside the pump and inside the pump. In the variousembodiments, the one or more thermistors and/or temperaturedetermination devices are preferably placed in the same location on thepump for use by the user as they were during the characterization.

In some embodiments, the characterization may be completed by measuringthe volume of fluid delivered as a function of temperature. In someembodiments, this may be accomplished by using a thermal chamber and aninfusion set/cannula connected to the reservoir/syringe delivering fluidto a precision scale. However, in other embodiments, this may completedby using a thermal chamber and an infusion set/cannula connected to thereservoir/syringe delivering fluid, and following, determining theposition of the plunger inside the reservoir to determine the totalvolume of fluid delivered.

In some embodiments, in practice, the temperature of the pump (in one ormore locations and/or taken by one or more thermistors) may be measuredand the target position of the plunger may vary as a function oftemperature to compensate for the thermal expansion of the syringeand/or the plunger. The thermal expansion reading may be determined byreferencing the characterization data, as discussed above. Thus, in someembodiments, the target position may be modified based on a look-uptable or function approximation of the volume change of the syringe withtemperature.

In some embodiments, the infusion pump delivers fluid either as a basalor a bolus delivery, and/or a variety thereof. The basal delivery is aprogrammed rate or volume per hour. The infusion pump delivers a volumeof fluid at preset intervals for preset durations of time. The infusionpump may also deliver bolus volumes. A bolus is a requested volume offluid delivered immediately, i.e., at the time the request is made. Oneembodiment of the bolus and basal delivery methods is described in PCTApplication Serial No. PCT/US2009/060158, filed Oct. 9, 2009 andentitled Infusion Pump Assembly, now Publication No. WO 2010/042814,published Apr. 15, 2010; and U.S. patent application Ser. No.12/249,882, filed Oct. 10, 2008 and entitled Infusion Pump Assembly, nowU.S. Publication No. US-2010-0094222, published Apr. 15, 2010 andentitled Infusion Pump Assembly, both of which are hereby incorporatedherein by reference in their entireties. Further, in some embodiments,for example, in the embodiment described in U.S. Pat. No. 7,498,563,issued Mar. 3, 2009 and entitled Optical Displacement Sensor forInfusion Devices, which is herein incorporated by reference in itsentirety, the infusion pump may determine the distance the plunger mustmove to deliver a volume of fluid, e.g., a basal volume or a bolusvolume. Thus, in some embodiments of the infusion pump system, theinfusion pump may confirm the distance the plunger moved during adelivery using an optical displacement sensor. In some embodiments, theinfusion pump determines the number of motor encoder counts per deliveryand confirms movements of the plunger.

However, in various embodiments, the delivery method includes adetermination of the distance the plunger should move (which may bereferred to as the target plunger position) to deliver thedesired/target volume. As discussed above, this may be done bydetermining the number of motor encoder steps, and in other embodiments,may be another method. Regardless, the infusion pump makes adetermination of plunger distance movement.

One example of the characterization and controls compensation method isas follows. The first step may be to characterize the volume deliveredas the temperature changes. This volume may be a function of the amountof fluid contained in the syringe, call this V, and, due to variationsin the thermal expansion properties of plastics and liquids/fluids,also, a function of the temperature, call this T. A function, β(T), maybe found empirically that related the volume change to the temperaturechange.

$\begin{matrix}{{\beta(T)} = {\frac{1}{V}\frac{\Delta\; V}{\Delta\; T}}} & \left. {{EQ}{\# 5}} \right\rbrack\end{matrix}$

The coefficient β(T) may be approximated as a constant, found as afunction of temperature (as shown above) or possible found as a functionof both temperature and plunger position β(T,x).

Next, the target plunger position may be determined and adjusted. Thetarget position, x, may be adjusted based on the following formula:

$\begin{matrix}{{\Delta\; x} = {\frac{{\beta(T)}V}{\frac{\pi}{4}D^{2}}\Delta\;{T.}}} & \left. {{EQ}{\# 6}} \right\rbrack\end{matrix}$

Where D is the plunger diameter. If we substitute in

$V = {\frac{\pi}{4}D^{2}x}$(assuming that x=0 where the plunger has reached the end of travel anddisplaced all of the fluid in the syringe) then the relationship may besimplified to:Δx=β(T)xΔT  [EQ#7]

In various embodiments, this correction may be performed in differentways, including, but not limited to, the following. In some embodiments,the correction may be done by delivering on an interval which may bemore frequent than the basal delivery interval, which may be, but is notlimited to, one delivery every e.g., 3 minutes, but in otherembodiments, may be more frequent or less frequent. Further, theposition of the syringe may be adjusted based on the temperature change,maintaining a zero net volume delivered between regular deliveries,e.g., basal and/or bolus deliveries. In some embodiments, this may beused for low basal rates, where the thermally driven volume may exceedthe regularly scheduled basal delivery. This may, however, in someembodiments, require reversing the syringe direction to preventdelivery.

Another embodiment may include applying the correction when thefluid/insulin is scheduled for delivery. Thus, the target plungerposition may be corrected based on the measured temperature change andestimated thermally-driven volume delivery. In some of theseembodiments, the correction may be limited such that the plunger mayonly be driven in one direction.

In some embodiments, modeling may vary, and an assumption may be madewith respect to both length and diameter of the syringe. In addition,assumption may be made regarding the effect of temperature on thethermal expansion coefficient of one or more components of the infusionpump, including, but not limited to, the drive train, plunger, plungerrod, infusion pump housing, and cannula.

In some embodiments, adjusting the plunger target may include adjustingthe target so that it is closer to the exit of the syringe, or furtheraway from the exit of the syringe. In some embodiments, the plungeradvancement may be modified. In other embodiments, the plunger may bedriven backwards to compensate for temperature. However, in someembodiments, depending on the infusion pump, it may be desired to limitadjustment to closer to the exit of the syringe. This may be due to thepotential for backlash.

In some embodiments, a temperature dependant basal rate may bepreprogrammed to the pump for temperature compensation. In theseexamples, the pump processor receives data from at least one temperaturesensor. If the temperature data indicates that the temperature is such,or that the rate of change of temperature is such, that an adjustmentshould be made, the processor may signal to alter the preprogrammedbasal rate. In some embodiments, this alteration may be either anadditional or a decrease of the basal rate by a preset percentage, forexample, an increase of 30% or a decrease of 15%. Of course, these areonly examples, and in these embodiments, the preset alterations may bedetermined to be different from those stated.

In some embodiments, the infusion pump may include at least onetemperature sensor and at least one optical sensor. In some embodiments,the optical sensor may be used to determine that the plunger advanced.In some embodiments, the distance of advancement may also be determined.In some embodiments, a small reflective optical sensor (hereinafter“optical sensor”) that fits into the form factor of the infusion pumphardware is used. The optical sensor has a sensing range that overlapswith the plunger displacements. In the exemplary embodiment any opticalsensor may be used, including, but not limited to a Sharp GP2S60,manufactured by Sharp Electronics Corporation which is a U.S. subsidiaryof Sharp Corporation of Osaka, Japan. This optical sensor contains aninfra red emitting diode and infra red sensing detector in a singlepackage. Light from the emitter is unfocused and bounces off the sensingsurface, some of which makes it back to the detector resulting in thesensed intensity of light that varies as a function of distance/angle tothe reflector. In some embodiments, the sensor is placed such that thereflective surface is the plunger.

In some embodiments, an optical sensor may be used to determine thelevel of fluid in the syringe/reservoir. This information may be used todetermine whether the plunger rod has advanced. Together with thetemperature sensor information, this may provide added data/informationto determine a temperature dependant change.

In some embodiments of the infusion pump system, including thoseembodiments disclosed and described in U.S. Pat. No. 7,498,563, issuedMar. 3, 2009 and entitled Optical Displacement Sensor for InfusionDevices; PCT Application Serial No. PCT/US2009/060158, filed Oct. 9,2009 and entitled Infusion Pump Assembly, now Publication No. WO2010/042814, published Apr. 15, 2010; and U.S. patent application Ser.No. 12/249,882, filed Oct. 10, 2008 and entitled Infusion Pump Assembly,now U.S. Publication No. US-2010-0094222, published Apr. 15, 2010 andentitled Infusion Pump Assembly, all of which are hereby incorporatedherein by reference in their entireties, the infusion pump may includean optical displacement sensor. This sensor may be used to determinewhether the plunger rod has advanced, either forward or backwards, andthe distance of the advancement. Using this displacement information,together with the information from the one or more temperature sensors,the effect of the temperature change on the plunger may be determined.In turn, this determination may increase the accuracy of controls usedto compensate for a temperature change. This may include, but is notlimited to, decreasing the amount of fluid delivered due to a sensedforward movement and/or increasing the amount of fluid delivered due toa sensed backwards movement. In either case, the increase and/or deceaseof the basal rate and/or amount and/or the amount of bolus (for example,by a percentage of the amount intended) is by a predetermined amount andfor a predetermined time.

In some embodiments, the infusion pump system may include a systemand/or method for adjusting the basal rate and/or bolus amount based ona temperature change. Thus, in various embodiments, where the systemdetermines that a threshold temperature change, either up or down, hasoccurred, the system may automatically, and/or by request and/orconfirmation by the user, enter a mode having a limited period, e.g., aflat pre-set limited time period, e.g., 20 minutes, and/or in someembodiments, the mode may continue until the temperature changethreshold is not longer applicable. In some embodiments, where, forexample, a decreasing temperature gradient is a primary concern, theinfusion pump processor may be pre-programmed with a “decreasinggradient” mode, and the infusion pump may purposefully under deliver inthis mode, i.e., an automatic percentage decrease in the basal rate,and, in some embodiments, also, the bolus, may be instituted tocompensate for a predicated additional delivery of fluid. As discussedabove, determining the percentage change of insulin delivery may dependon the characterization of the infusion pump.

Following, in some embodiments, where, for example, increasingtemperature gradient is the primary concern, the infusion pump processormay be pre-programmed with a “increasing temperature gradient” mode, andthe infusion pump may purposefully over deliver, i.e., an automaticpercentage increase in the basal rate, and, in some embodiments, alsothe bolus, may be instituted to compensate for the predicated decreasein delivery of fluid. As discussed above, determining the percentagechange may depend on the characterization of the infusion pump.

Closed loop Temperature Compensation

For the purposes of this description, the term “advanced” refers to themovement of a plunger within a syringe or reservoir body. Advancement isnot limited to movement in a particular direction. The syringe has anexit end, which is the end of the syringe in which fluid moves outwardfrom the syringe.

In some embodiments, the system may include one or more devices and/orsensors to determine the effect of the temperature on thesyringe/plunger and/or the pumping of fluid, either towards theuser/cannula or away from the user/cannula. These devices and/or sensorsmay include, but are not limited to, one or more flow sensors, one moreocclusion devices and/or one or more binary valves, and/or one or morestrain beams or sensors and/or one or more optical sensors and/or one ormore temperature sensors and/or one or more ultrasonic range sensorsand/or one or more potentiometers and/or one or more rotor encodersand/or one or more linear encoders.

With respect to optical sensors, in some embodiments, the infusion pumpmay include at least one temperature sensor and at least one opticalsensor. In some embodiments, the optical sensor may be used to determinethat the plunger advanced. In some embodiments, the distance ofadvancement may also be determined. In some embodiments, a smallreflective optical sensor (hereinafter “optical sensor”) that fits intothe form factor of the infusion pump hardware is used. In variousembodiments, the optical sensor has a sensing range that overlaps withthe plunger displacements. In various embodiments any optical sensor maybe used, including, but not limited to one or more of the following:Sharp GP2S60, Sharp GP2S700 and Sharp GP2A240LC, all of which aremanufactured by Sharp Electronics Corporation which is a U.S. subsidiaryof Sharp Corporation of Osaka, Japan. This optical sensor contains aninfra red emitting diode and infra red sensing detector in a singlepackage. Light from the emitter is unfocused and bounces off the sensingsurface, some of which makes it back to the detector resulting in thesensed intensity of light that varies as a function of distance/angle tothe reflector. In some embodiments, the sensor is placed such that thereflective surface is the plunger.

In some embodiments, an optical sensor may be used to determine thelevel of fluid in the syringe/reservoir. This information may be used todetermine whether the plunger rod has advanced. Together with thetemperature sensor information, this may provide added data/informationto determine a temperature dependant change.

In some embodiments of the infusion pump system, the infusion pump mayinclude an optical displacement sensor. This sensor may be used todetermine whether the plunger rod has advanced, either forward (towardsthe syringe exit) or backwards (away from the syringe exit), and thedistance of the advancement. Using this displacement information,together with the information from the one or more temperature sensors,the effect of the temperature change on the plunger may be determined.In turn, this determination may increase the accuracy of controls usedto compensate for a temperature change. This may include, but is notlimited to, decreasing the amount of fluid delivered (i.e., decreasingthe volume of fluid that was scheduled to be delivered, i.e., basalrate, or requested to be delivered, i.e., bolus amount) to a sensedforward movement and/or increasing the amount of fluid delivered due toa sensed backwards movement.

In some embodiments, the infusion pump may include an exit valve and/oran occluder. Thus, in these embodiments, the infusion pump includes atleast one device to prevent the delivery of fluid either from thesyringe to the cannula and/or from the cannula to the user. In someembodiments, the device is activated when the at least one temperaturesensor sends a signal to the processor and the processor determines thatthe temperature change meets a threshold, i.e., that the temperaturechange is large enough to effect a change in delivery due totemperature. In some embodiments, this may activate the occluder and/orexit valve, preventing fluid from flowing into or out of the syringeand/or the cannula. In some embodiments, the occluder and/or exit valvedevice is deactivated when the at least one temperature sensor sends asignal to the processor and the processor determines that thetemperature change no longer meets a threshold, i.e., that thetemperature change is no longer large enough to effect a change indelivery due to temperature. In some embodiments, this may deactivatethe occluder and/or exit valve, allowing fluid to flow out of thesyringe and/or to the cannula and/or to the user. Again, as discussedabove, in some embodiments, the plunger target may be adjusted inresponse to the information from one or more temperature sensors.

In some embodiments, the occluder/exit valve may be closed during theinterval when the infusion pump is not actively delivering fluid so asto prevent inadvertent fluid flow in or out of the syringe/reservoir dueto a change in temperature. During the time when the infusion pump isnot actively delivering fluid, the at least one temperature sensor maycontinue to send signals to the processor indicating temperature. Thisinformation may be used by the control system to determine whether andhow to modify the “next delivery” of fluid, i.e., the next plungertarget. Thus, when the “next delivery” is made, the occluder/exit valvemay open and the fluid is delivered.

Thus, in these embodiments, the occluder/exit valve may act primarily toprevent spontaneous unintended fluid flow that may be caused bytemperature change. The control system may adjust the volume delivery,i.e., plunger target, based on the temperature change such that thevolume of delivered fluid compensates for the temperature change.

In some embodiments, the infusion pump may include a compliantcomponent. In some embodiments, the compliant component may allow thedifference in volume change in the syringe/reservoir while maintaining apressure constant. Thus, in these embodiments, controller compensationmay not be necessary to compensate for temperature change when theoccluder/exit valve is open as there would not be a pressure build upfrom a change in temperature.

In some embodiments, once a threshold temperature change has beendetermined, the occluder/exit valve may be closed and the plunger rodmay be allowed to float, i.e., the plunger rod may become disengagedwith the drive train. A change in pressure would thus allow the plungerto float and find equilibrium, thus adjusting without the need forcontroller compensation in response to a temperature change.

In some embodiments, the infusion pump may include at least one flowsensor, including, but not limited to, a flow sensor positioned in theexit fluid path. The flow sensor may detect the flow of fluid. Thisinformation may be correlated with delivery instructions and adetermination may be made whether the fluid delivered was requestedand/or a proper delivery. In some embodiments, where flow is detectedand it is determined that the fluid delivered was not requested and/ornot a proper delivery, the occluder and/or exit valve may be closed.Thus, in some embodiments, a flow sensor may determine fluid flow,either inward or outward, and where this is not an expect event, theinfusion pump may activate at least one mechanism, including, but notlimited to, an occluder and/or a valve to prevent the continued flow offluid. Additionally, the flow information may be used to determine theamount or volume of fluid that has been delivered or has flowed inwardand this information may be used to alter the plunger target during thenext scheduled or requested delivery (e.g., basal or bolus), or, in someembodiments, may be used to alter the delivery schedule. In someembodiments, this may be completed without user interaction. In someembodiments, an alert may be sent to the user and the user must acceptthe proposed course or action to alleviate the under or over delivery offluid.

In some embodiments, the infusion pump may include one or more opticalsensors. These sensors may be placed in the infusion pump to determinethe level of fluid in the syringe/reservoir. The one or more opticalsensors may determine the level of fluid before the processor signalsthe drive train to advance the plunger and after. Thus, the volumedifference may be determined before and after the plunger is advanced.However, the at least one optical sensor may, in some embodiments,collect data a preset intervals, regardless or whether the drive trainhas been activated. Thus, the at least one optical sensor may collectinformation to determine when and whether the plunger has advancesand/or when and whether fluid has been delivered or pulled in. Thus, theat least one optical sensor may collect data for the processor todetermine when a non-requested delivery event may have occurred. Theprocessor may correlate this information with the at least onetemperature sensor and thereby determine whether the infusion pump isexperiencing a temperature related effect. In some embodiments, theprocessor may alert the user. In some embodiments, the information maybe used to instigate a control algorithm to compensate for thetemperature change effect using, for example, but not limited to, thevarious embodiments discussed herein.

In some embodiments, a strain beam may be used to identify a plungermoving away from the exit of the syringe. In these embodiments, thestrain beam may be positioned relative to the plunger rod such thatwhere the plunger rod begins to move away from the syringe exit, thestrain beam will sense the strain. In some embodiments of the infusionpump system, the infusion pump includes a strain beam that may be usedto detect and/or identify occlusions. The strain beam and methods maybe, in some embodiments, similar to those described in U.S. patentapplication Ser. No. 12/249,882, filed Oct. 10, 2008 and entitledInfusion Pump Assembly, now U.S. Publication No. US-2010-0094222,published Apr. 15, 2010, and PCT Application Serial No.PCT/US2009/060158, filed Oct. 9, 2009 and entitled Infusion PumpAssembly, now Publication No. WO 2010/042814, published Apr. 15, 2010,which are hereby incorporated herein by reference in their entireties.However, together with the at least one temperature sensor, a strainbeam may determine whether a particular temperature change has resultedin plunger movement. Where plunger movement is detected due to atemperature change, the infusion pump may alert the user. In someembodiments, the system may correlate a change in strain with a changein temperature.

Temperature Maintenance

As discussed above, there may be a desire to maintain the temperature ofan infusion pump to avoid any consequences from a temperature change. Insome embodiments, to minimize or prevent the above-described effects oftemperature changes on the infusion pump and delivery of fluid, one ormore various apparatus and/or systems may be employed to maintain thetemperature of the infusion pump.

In some embodiments, the infusion pump includes a heater device. Theheater device may receive instructions from the processor. The heaterdevice may be located anywhere in or on the infusion pump, however, insome embodiments, the heater device is located within the infusion pumphousing. In some embodiments, the heater device is powered by a powersource or battery inside the infusion pump. However, in someembodiments, the power source may be outside the infusion pump.

The heater source may be any heating source desired, however, in theexemplary embodiment, the heating source may be a KAPTON® (PolyimideFilm) Heater kit, part number KH-KIT-EFH-15001 and available fromOmega.com®. In some embodiments, at least one temperature sensor islocated in or on the infusion pump. The at least one temperature sensorcommunicates information to the processor. Based on the temperaturesensor data, the processor may act as a thermostat and power the heatersource to maintain the temperature in the infusion pump at a desiredtemperature. In some embodiments, the desired temperature may be between15 and 30 degrees Celsius, but in other embodiments, the maintenancetemperature may be different. In some embodiments, it may be desirableto maintain the temperature at the higher end.

In some embodiments the syringe/reservoir may be contained in a metalcase in the infusion pump. The metal case may increase the conduction ofheat between the heater element and the syringe/reservoir.

In some embodiments, the at least one heater element may be located inone or more locations inside the infusion pump and one or more of theselocations may be selected to maintain the temperature of one or morecomponents of the infusion pump, including, but not limited to, thesyringe, fluid, plunger, housing, plunger rod and/or the drive train.

In some embodiments, the at least one heater elements may additionallyincrease the power source and/or battery life in the infusion pump.Maintaining the temperature at or about 35 degrees Celsius may bebeneficial to battery life and/or performance.

In some embodiments, it may be desirable to utilize the user's body as aheat sink, wearing the infusion pump close to the user's skin. This maybe accomplished using various devices and apparatus, including but notlimited to one or more of the following.

A hook and loop system fastener system, for example, but not limited toone offered by VELCRO® USA Inc. of Manchester, N.H., may be utilized toallow for easy attachment/removal of an infusion pump from the user.Accordingly, an adhesive patch may be attached to the skin of the userand may include an outward facing hook or loop surface. Additionally, asurface of infusion pump 114 may include a complementary hook or loopsurface. Depending upon the separation resistance of the particular typeof hook and loop fastener system employed, it may be possible for thestrength of the hook and loop connection to be stronger than thestrength of the adhesive to skin connection. Accordingly, various hookand loop surface patterns may be utilized to regulate the strength ofthe hook and loop connection.

Referring also to FIGS. 4A-4E, five examples of such hook and loopsurface patterns are shown. Assume for illustrative purposes that onesurface of infusion pump housing is covered in a “loop” material.Accordingly, the strength of the hook and loop connection may beregulated by varying the pattern (i.e., amount) of the “hook” materialpresent on the surface of adhesive patch. Examples of such patterns mayinclude but are not limited to: a singular outer circle 220 of “hook”material (as shown in FIG. 4A); a plurality of concentric circles 222,224 of “hook” material (as shown in FIG. 4B); a plurality of radialspokes 226 of “hook” material (as shown in FIG. 4C); a plurality ofradial spokes 228 of “hook” material in combination with a single outercircle 230 of “hook” material (as shown in FIG. 4D); and a plurality ofradial spokes 232 of “hook” material in combination with a plurality ofconcentric circles 234, 236 of “hook” material (as shown in FIG. 4E).

In another embodiment, a holder, pouch, sack, container or other type ofhousing (generally referred to as a “holder”) may be sized toaccommodate an infusion pump. In some embodiments, the holder may beconstructed to include multiple layers including but not limited to, oneor more insulating layers. In some embodiments, one or more of thelayers may include a fabric that when wetted and refrigerated or frozen,the layer provides a cooling effect. This layer may be desired in warmerclimates or in situations where the user's infusion pump may be exposedto the sun or a warm environment. In some embodiments, the one or morelayers of material may be highly absorbent material. In someembodiments, the holder may include one or more canisters of isopropylalcohol which may, when deployed, be absorbed into the highly absorbentmaterial of the holder and provide evaporative cooling to the infusionpump. In various embodiments, the holder may include alternative and/oradditional methods, systems and/or devices for cooling the infusionpump.

In some embodiments, the holder may include one or more temperaturemeasurement devices and/or temperature sensors that may transmitinformation to the infusion pump and/or a controller. The one or moretemperature sensors may communicate the temperature of the holder andeither deploy the one or more canisters of alcohol and or alert theinfusion pump/user/controller and/or turn o the heating source, based onthe temperature sensor. In some embodiments, the heating and/or coolingmay be triggered by reaching a threshold change in temperature. Thus, insome embodiments, the holder may provide for a closed-loop system formaintaining the temperature for the infusion pump.

Referring now to FIG. 5, some embodiments of the holder 500 include anoutside layer 502, an inside layer 504 and an inner pocket 506. Thepocket 506 may include additional cushion or insulation to both protectthe infusion pump from outside forces and/or temperature change. Theholder 500 may include a fastener along the front, top or the side. Insome embodiments, the holder 500 may include the holder may include apull down flap (not shown) on the front to expose the screen and/orinput assemblies (e.g., including but not limited to buttons, sliders,and/or jog wheels). In some embodiments, the flap may be secured closedusing a hook-and-loop system. In other embodiments, the flap may besecured using any other fastener system including, but not limited to,snaps, buttons, magnetic closures and zippers.

In some embodiments, the holder 500 may be attached to a strap 508designed to be attached to the user (see FIG. 6 for example). However,in various embodiments, the strap 508 may be elastic and/or adjustableand may include at least one closure device. Although shown in FIG. 6 asbeing worn about the mid section of a user 510, the holder 500 may beworn anywhere the user desires.

Referring now to FIG. 7, an embodiment of the back of the holder 500 isshown. In some embodiments, the holder may include a clip 512 which maybe referred to as a “belt-clip” or another type of clip configured suchthat it securely and removably fits over a belt, handle, piece ofclothing or other. In some embodiments, the holder 500 may additionallyinclude an opening 514 for tubing 516 to fit through. In someembodiments, the infusion pump (not shown) may be contained inside theholder 500 and the holder worn close to the insertion site (not shown)on the user such that minimal tubing 516 is exposed to the outsidetemperature. Thus, embodiments of the holder 500 including an opening514 for tubing may be beneficial for maintaining the temperature of thetubing 516 and/or the fluid in the tubing.

In some embodiments, a plastic material for example, a Press n' Seal, oranother material of similar behavior, may be used to attach and maintainthe infusion pump against the user's body. In other embodiments, a cuffor band fitted against the leg, midsection or arm, for example, of auser may include a pouch for the infusion pump. In other embodiments,the infusion pump may be maintained in position against the skin throughinner pockets, bra pockets, etc.

Various embodiments are described herein for both utilizing the user'sbody heat and/or a heating element to maintain the temperature of theinfusion pump. However, additional devices and apparatus are within thescope of the invention. Further, various methods, systems and apparatusfor maintaining the temperature of an infusion pump may include at leastone temperature sensor.

Insulin Temperature

Described herein are various methods, systems, devices and/or apparatusfor maintaining the temperature of an infusion pump. Inherent in atleast some of these embodiments is the maintenance of the infusiblefluid/insulin temperature. It is well know that manufacturers of insulinrecommend that the temperature of insulin not exceed a high and a lowtemperature. Additionally, it may be beneficial to maintain fast-acting(e.g., HUMALOG®, NOVOLOG®) at room/ambient temperature (e.g., between 59and 86 degrees Fahrenheit) once the vial has been used, i.e., themanufacturer recommends storing insulin in a refrigerated area, e.g.,between 36 and 46 degrees Fahrenheit, until the vial is used. From thatpoint on, it is recommended that the vial be stored at room temperature.

As insulin may be less effective or not effective once it has reached anon-recommended temperature, it may be beneficial for a user to knowwhether the insulin has been properly stored, whether while in transit,in the refrigerator or while in use.

Referring to FIG. 8, in one embodiment, a stick-on temperature gauge 520may be placed on a vial 522 of fluid, and in some embodiments, on a vialof insulin. The gauge may tell the user the current temperature of thevial. In some embodiments, the temperature may be indicated as variousshades of red and blue, indicating various temperatures towards the highand low range. In some embodiments, once the temperature has reachedeither the maximum or minimum temperature (which is predetermined andmay, in some embodiments, be 35 and 87 Fahrenheit respectively), thegauge becomes non-reversible, thus indicating instantly to the user thatthe insulin has reached either a maximum or minimum temperature.

Any stick-on temperature gauge may be used including a non-reversibletemperature label such as a Non-Reversible Temperature Labels, 3Temperature Ranges, part number TL-3 available from Omega.com®, oranother similar temperature label. As discussed above, in someembodiments, a Reversible Temperature Label may be used or a label withboth reversible and non-reversible components

Atmospheric Pressure

A decrease in atmospheric pressure may result in unintentional and/orunscheduled and/or non-requested delivery of fluid from a reservoir inan infusion pump to a user. A decrease in pressure effects air that maybe in the reservoir and/or may be dissolved in the fluid in thereservoir. Some embodiments of infusion pumps which may be affected aresyringe infusion pumps and those similar to a syringe infusion pump,which may include, but is not limited to, various embodiments shown anddescribed in U.S. Pat. No. 7,498,563 issued Mar. 3, 2009 and entitledOptical Displacement Sensor for Infusion Devices; U.S. Pat. No.7,306,578 issued Dec. 11, 2007 and entitled Loading Mechanism forInfusion Pump; and PCT Application Serial No. PCT/US09/060,158 filedOct. 9, 2009 and entitled Infusion Pump Assembly, now Publication No.WO2010/042814, published Apr. 15, 2010 which are all hereby incorporatedherein by reference in their entireties, and shown in FIGS. 1A-3. Thus,in operation, where the syringe infusion pump experiences an atmosphericpressure decrease, an unintended bolus may be delivered to a user. Thispresents a safety concern as the unintended bolus may also be unknown tothe user. Thus, the user may experience an over delivery event which, inthe embodiments including an insulin pump, may result in a hypoglycemicevent.

An increase in atmospheric pressure may result in an unintentionaland/or unscheduled siphoning of fluid from the tubing/cannula towardsthe reservoir in an infusion pump. Some embodiments of infusion pumpswhich may be affected are those similar to a syringe infusion pump,which may include, but is not limited to, various embodiments shown anddescribed in U.S. Pat. No. 7,498,563 issued Mar. 3, 2009 and entitledOptical Displacement Sensor for Infusion Devices: U.S. Pat. No.7,306,578 issued Dec. 11, 2007 and entitled Loading Mechanism forInfusion Pump; and PCT Application Serial No. PCT/US09/060,158 filedOct. 9, 2009 and entitled Infusion Pump Assembly, now Publication No.WO2010/042814, published Apr. 15, 2010, and FIGS. 1A-3. Thus, inoperation, where the syringe infusion pump experiences an atmosphericpressure increase, an unintended siphoning of fluid from thetubing/cannula may occur which may result in a less than intended volumedelivered to a user. This presents a safety concern as the siphoningvolume may also be unknown to the user. Thus, the user may experience anunder delivery event which, in the embodiments including an insulinpump, may result in a hyperglycemic event.

In some embodiments, the syringe infusion pump and/or the remotecontroller for the syringe infusion pump may include a pressure sensor,which in some embodiments may be an altimeter, similar to those known inthe art. The terms “pressure sensor” and altimeter” may be usedinterchangeably herein. The altimeter may be in communication with thepump processor and therefore, the data from the altimeter may be used bythe pump processor. In some embodiments, the processor may includepredetermined rate of change and/or atmospheric pressure thresholds(either increases or decreases) that trigger at least one response fromthe infusion pump.

In some embodiments, the response may include notification to the user.Thus, the infusion pump and/or a remote controller may notify and/oralarm and/or alert the user where the altimeter sends data indicating anincrease and/or a decrease in atmospheric pressure which has triggered athreshold. In some embodiments, the processor may recognize, from thealtimeter data, potential events, e.g., airplane take-off, airplanedecent, traveling to/from high altitudes to low altitudes. Theserecognized events may, in some embodiments, trigger at least one commentto the user, for example, the pump and/or controller may alert and/oralarm the user with a question, which may include, for example, but isnot limited to, “airplane take-off?” and/or “airplane decent?”. Uponconfirmation by the user, the pump may suggest, e.g., by an alert and/oran alarm e.g., either by an audio and/or visual signal to the user, thatthe user disconnect from the cannula. Following, when altimeter dataindicates that a threshold “safe” altitude has been reached and/or theuser is at an appropriate altitude for a predetermined period of time,the pump/controller may alert and or alarm the user to reconnect to thecannula. Thus, in some embodiments, any potential adverse effects causedby atmospheric pressure changes may be minimized and/or mitigated andfor avoided by notification to the user followed by user disconnectand/or reconnect as appropriate.

Referring now also to FIG. 9, a method for atmospheric pressuremitigation 600 is shown. In some embodiments, the pressuresensor/altimeter sends data to a processor at predetermined intervals602. If the altimeter data indicates a predetermined alert and/or alarmthreshold 604, the processor may alert and/or alarm the user todisconnect from the cannula 606. When the altimeter indicates apredetermined appropriate/safe threshold has been met 608, the processormay alert and/or alarm the user to re-connect to the cannula 610.However, until the predetermined appropriate threshold has been met 608,the altimeter continues to send data to the processor at predeterminedintervals 612.

In some embodiments, the altimeter may send data to the processor atpredetermined intervals which may be, but is not limited to, everyminute. In some embodiments, the frequency may increase or decreasedbased on altimeter data. For example, in some embodiments, whereairplane take-off is confirmed by the user, the altimeter may send datato the processor more frequently. In some embodiments, once the user hasreconnected, the altimeter may send data to the processor based onentered events by the user. For example, in some embodiments, where theuser foresees airplane travel, (airplane travel is used merely as anexample, in other embodiments, the event may be any event which mayresult in a change in atmospheric pressure) the user may select eitheron the pump and/or the controller, a menu option in the user interfaceto indicate to the pump to be placed in “airplane mode”. This mode mayalso request the user to enter additional information, for example,scheduled take-off time, and/or scheduled landing time. Thus, the pumpand/or controller may modify the frequency of the altimeter datacommunication based on user input information. The user inputinformation may additionally be used by the pump and/or controller torecognize chances in the events through readings from the altimeter. Forexample, the processor may recognize that where a decrease inatmospheric pressure may be anticipated based on a user entered take-offtime is not realized, the pump/controller may request furtherinformation from the user regarding changed take-off time. The userentered event information may additionally be used by the processor toconfirm and altimeter function and/or accuracy. For example, where areading during take-off is not as expected, even within a preprogrammedmargin of error, the pump/controller may alarm/alert as this mayindicate a malfunction of the altimeter. In some embodiments, thepump/controller may then alert the user to disconnect during take-offand decent.

In some embodiments, the data from the altimeter and/or data from apressure sensor may be used to modify the scheduled delivery of fluid.Thus, the altimeter and/or pressure sensor may be in communication withthe infusion pump processor. A sensed changed in pressure, either in apositive or negative direction, may be communicated to the processor. Inresponse, the processor may communicate to the controller to eitherdecrease or increase the rate of delivery of the infusible fluid. Forexample, the controller may increase or decrease any scheduled deliveryfor a predetermined period of time by a predetermined percentage. Insome embodiments, the infusion pump may include a mode or otherpreprogrammed delivery schedule modifier to address situations where theinfusion pump may experience an increase or decrease in pressure whichmay effect the delivery of fluid. The mode may be selected by a userwhen the user is experiencing or plans to experience a change inpressure event, for example, but not limited to, flying in an airplane.The user may select the mode which may be termed an “airplane mode” insome embodiments (however, this is merely an example of a name and also,the term may be used to identify any change in pressure event in variousembodiments and in various embodiments is not limited to airplaneevents), and may additionally specify whether taking off or landing, forexample. In response, the infusion pump may increase or decrease therate of delivery.

In some embodiments, where the altimeter data indicates a change inpressure event which may result in an unintentional/unintended increaseor decrease in fluid delivery, and/or where the user has indicated sameto the pump and/or controller, for example, but not limited to, one ormore of the following, through menu selection and/or manual entryand/voice recognized command, the pump may enter an “airplane mode”which may, in some embodiments, include a modification of the frequencyof determination of the location of the plunger. In some embodiments,for example, as described above and/or in U.S. Pat. No. 7,498,563 issuedMar. 3, 2009 and entitled Optical Displacement Sensor for InfusionDevices, the infusion pump may include at least one sensor fordetermining the location of the plunger. Although, in some embodiments,this may be accomplished by using the methods, apparatus and systemsdescribed above, and/or in U.S. Pat. No. 7,498,563 issued Mar. 3, 2009and entitled Optical Displacement Sensor for Infusion Devices, in otherembodiments, other sensors for determining plunger movement or plungerlocation may be used. However, in the various embodiments, the frequencyat which the sensor determines the position of the plunger may vary in“airplane mode”. For example, in some embodiments, during normaloperation, the infusion pump may determine the position of the plungerbefore and after a scheduled and/or requested delivery. However, in someembodiments, in airplane mode, to determine a movement of the plungerwhich may not be due to a scheduled and/or requested delivery, theinfusion pump may modify the frequency of the sensor readings todetermine the volume of fluid either siphoned or delivered due to achange in pressure event. Thus, upon entering airplane mode and/or uponthe altimeter data triggering the mode, the sensor may take readings atpredetermined intervals, every 1 minute. In some embodiments, where thesensor readings indicate a movement either towards delivery orsiphoning, an estimated volume of fluid either delivered or siphoned maybe presented to the user. Thus, the user may make appropriate changes intherapy based on this information. In some embodiments, however, thesensed volume of fluid either delivered and/or siphoned may be used bythe processor to modify the scheduled deliveries for a predeterminedperiod of time. In some embodiments, the predetermined period of timemay be dependant on many factors, including, but not limited to, thevolume of fluid for which the infusion pump is correcting.

Referring to the description above with respect to temperature changesand mitigation, in some embodiments, a similar mode regarding sensingthe position of the plunger may be entered into automatically and/ormanually upon a change of pressure threshold being met. Thus, thevarious methods described regarding the various embodiments pertainingto sensor frequency modification and downstream modification of deliverymay be used for pressure mitigation.

In some embodiments, the infusion pump may include at least one valvelocated downstream from the reservoir. In various embodiments, the valvemay be located anywhere between the distal side of the reservoir to thecannula site, including, but not limited to, built into the infusion setitself, including but not limited to one or more of the following: inthe tubing, in the cannula, and/or on the distal end of the reservoir.In some embodiments, the at least one valve may be apressure/atmospheric compensation valve. In some embodiments, the valvemay be a micro check valve similar to the one shown in Appendix A (Lee250 Zero Leak Chek® available from The Lee Company, Westbrook, Conn.,USA), configured such that the valve remains fully closed with anypressure differential that is higher on the cannula side of the valvecompared with the reservoir side of the valve (which may also bereferred to as “downstream from the valve” and “upstream of the valve”respectively), i.e., when the valve is closed, no fluid may flow back tothe reservoir. In some embodiments, the outflow cracking pressure may beselected such that a differential pressure related to the change inaltitude would not cause the valve to open. For example, in someembodiments, the cracking pressure may be set to 5 PSI. Thus, in thisembodiment, at sea level, the infusion pump may be required to generate5 PSI to induce flow. During, for example, pressure decreases, such asthose experienced during airplane flight, the infusion pump may berequired to induce 1 PSI, for example, to induce flow due to thenegative pressure bias of the altitude change. In some embodiments,fluid flow based on altitude changes alone may be eliminated and/ordecreased and/or mitigated. Thus, in embodiments such as these, theeffect of pressure changes may be mitigated while the user receives theintended and or scheduled and/or requested therapy deliveries.

Air Bubble Management

Air bubbles and/or air dissolved in the fluid in a syringe reservoirsimilar to the ones shown and described in U.S. Pat. No. 7,498,563,issued Mar. 3, 2009 and entitled Optical Displacement Sensor forInfusion Devices; U.S. Pat. No. 7,306,578, issued Dec. 11, 2007 andentitled Loading Mechanism for Infusion Pump; and PCT Application SerialNo. PCT/US2009/060158, filed Oct. 9, 2009 and entitled Infusion PumpAssembly, now Publication No. WO 2010/042814, published Apr. 15, 2010,may affect fluid delivery. Air bubbles and/or dissolved air in the fluidde-gassing, displaces fluid, and may expand and/or be compressed, whichmay effect delivery. Additionally, air bubbles may affect occlusiondetection in some embodiments of infusion pumps. For example, with manyinfusion pump systems, occlusion detection is performed using a strainbeam/strain gauge to detect the upstream pressure exerted from theplunger towards the strain beam. When the pressure reaches a threshold,an occlusion is determined and/or assumed by the system and generally,an occlusion alarm and/or alert is given to the user. However, thisocclusion detection system relies on the fluid in the reservoir beingnon-compressible.

When the fluid in the reservoir includes at least one air bubble, as airis compressible, additional force within the reservoir, due to anocclusion, must first compress the air bubbles prior to the force beingexerted onto the strain gauge. This may ultimately require more force bepresent to detect an occlusion. Thus, air bubbles in the reservoir maycontribute to a delay in occlusion detection. Therefore, for manyreasons, including occlusion detection, it may be desirable to minimize,mitigate and/or eliminate air bubbles and/or dissolved air in the fluidin the reservoir.

Additionally, as air bubbles increase in size, they may increase thefluid pressure within the reservoir. Increased fluid pressure within thereservoir may cause unintentional and/or unscheduled delivery of avolume of fluid (which, in some embodiments, is insulin).

Mitigation of Over-Delivery Caused by Air With respect to mitigation ofair bubbles to minimize and/or eliminate unintentional and/orunscheduled fluid delivery, in some embodiments, a three-way valve maybe located downstream from the reservoir. Referring now to FIG. 10, insome embodiments, both an active check valve 650 and a passive checkvalve 652 may be located downstream from the reservoir 654. In someembodiments, the active check valve 650 may be opened for intendedand/or scheduled and/or requested therapy deliveries but otherwise,remain closed. The passive check valve 652 may be cracked only whensufficient pressure is exerted on the valve to overcome the valve. Thus,in some embodiments, when there are no intended and/or scheduled and/orrequested therapy deliveries, the active valve 650 remains closed. Thiscontinues unless and until the fluid pressure is sufficient to overcomethe passive check valve 652, thus, no fluid will pass through eithervalve. However, in some cases, increased fluid pressure, e.g., from anair bubble, may overcome the passive check valve 652 (i.e., may overcomethe cracking pressure of the passive check valve 652) and flow outsideof the pump (and in various embodiments, the fluid flowing through thepassive check valve 652 may flow anywhere desired except to the user).Thus, in this embodiment, only intended and/or scheduled and/orrequested therapy deliveries will be made, otherwise, increased fluidpressure may be mitigated (and unintended and/or unscheduled fluiddeliveries avoided and/or mitigated and/or decreased) through use of apassive check valve 652.Air Bubble Minimization

Air bubbles may be introduced into the reservoir by various methods anddue to various circumstances, including, but not limited to, fluidout-gassing. In some cases, the fluid may out-gas after being introducedinto the reservoir. This may occur as a result of temperature. In somecases, for example, where insulin is used as the fluid, insulin that isbelow room temperature may experience a certain amount of out-gassingwhile coming to room temperature. Comparatively, insulin that is and hasbeen at room temperature for a period of time may not experience as muchout-gassing, thus, insulin in this state may undergo minimal or lessout-gassing in the reservoir as compared with insulin that was belowroom temperature when loaded into the reservoir.

Therefore, a method, system and apparatus for increasing the out-gassingof insulin and/or a fluid prior to loading into the reservoir may bedesired. This may minimize the effects of out-gassing, that is, minimizethe effects of air bubbles in the reservoir.

Referring now to FIG. 11, in some embodiments, a fill adapter device 700may be used to minimize the effects of out-gassing. In some embodiments,the fill adapter 700 may be a reusable fill adapter, however, in otherembodiments; the fill adapter 700 may be disposable. In someembodiments, the fill adapter 700 device may be connected to the vial702 (i.e., configured to be connected and/or removably attached to avial) of infusible fluid to be used while filling and/or partiallyfilling a reservoir/syringe 704 with infusible fluid which in someembodiments is insulin. In some embodiments, the fill adapter 700 may beattached and/or removably attached to the vial 702 at manufacture and insome embodiments; a user may attach the fill adapter 700 at the time ofuse (and in some of these embodiments, the fill adapter 700 may beremovably attached). In some embodiments, therefore, a vial 702 may beprovided together with the fill adapter 700 and in some embodiments, thereservoir 704 may be provided to a user together with the fill adapter700. In other embodiments, the fill adapter 700 may be a separate devicefrom the vial 702 and/or reservoir 704. In some embodiments, the filladapter 700 may additionally include a needle (not shown) connecting thefluid from the vial to the fluid pathway 712. In some embodiments, asthe fill adapter 700 is being attached to the vial 702, the needle

The device may include a heat exchanger which may include a heatingelement 706 and a fluid pathway 712, for example, but not limited to, alength of tubing/fluid pathway (which may be made from glass and/orplastic or any fluid compatible material). The fluid pathway 712 may befluidly connected to a septum and/or a filling needle input 714. In someembodiments the length of tubing may be any length and/or diameter tomost efficiently and effectively induce out-gassing. While filling thereservoir/syringe 704 (which may, in some embodiments, include at leastone plunger 708), the fluid enters and passes through the heat exchangerincluding the fluid pathway 712 which is heated by the heating element706 where it may be heated to a predetermined temperature. While beingheated to the predetermined temperature, out-gassing may occur.

Some embodiments of the fill adapter 700 include a heat source and/orheating element 706. In various embodiments, the heating element 706 maybe any heating element known in the art which may include, but is notlimited to the following, inductive, optical, RF, microwave, electricalor other.

In some embodiments, the fluid path 712 and/or the fill adapter 700 maybe designed to heat the fluid at a desired and/or predetermined rate.Thus, in some embodiments, there may be additional features on the filladapter 700 to control the rate of heating of the fluid and or the flowrate of the fluid through the heating element 706. These may include,but are not limited to, a pump and/or an active valve.

In some embodiments, the fluid may be heated to room temperature. Inother embodiments, the fluid may be heated to less than room temperatureand in still other embodiments; the fluid may be heated to above roomtemperature. In some embodiments, the fill adapter 700 may include aprocessor (not shown) which may control the heating of the fluidaccording to one or more preprogrammed profiles. The one or moreprofiles may be designed for various situations and/or various types offluids. Depending on the desired temperature, the heat exchanger and/orthe fill adapter 700 may be designed accordingly.

Thus, in various embodiments, use of an embodiment of the fill adapter700 may act to accomplish at least, but not limited to, one or more ofthe following: minimize, decrease and/or eliminate downstream effects ofout-gassing; minimize, decrease and/or eliminate the subjective amountof out-gassing such that the amount of out-gassing is controlled and/orpredictable and therefore may be mitigated through other means;decrease, minimize, eliminate and/or lessen the occurrence ofout-gassing; stabilize the temperature of the fluid to minimizepotential effects of the temperature increase between, for example,refrigerated temperature and room temperature; decrease, eliminate,and/or minimize and/or lesson the effects of out-gassing in thereservoir 704, including but not limited to, volume changes in thereservoir 704.

In some embodiments, there may be an air trap and/or a hydrophobicfilter (not shown) or other to allow the escape of the air from the heatexchanger. Thus, while the fluid is heated to the predeterminedtemperature out-gassing occurs and therefore may minimize out-gassingwhich may otherwise have occurred after filling a reservoir and/orsyringe 704.

In some embodiments, a heating apparatus (not shown) may be used to heatthe reservoir 704 following fill and/or partial fill (the term “fill”may be used to refer to the transfer of any volume of fluid into thesyringe/reservoir, regardless or whether the volume of fluid reachesmaximum capacity or partial capacity) of the reservoir 704. The heatingapparatus may be a nondisposable/reusable type apparatus which mayinclude a heating element, e.g., inductive, optical, RF, microwave,electrical or other. The heating apparatus may be configured such thatthe filled reservoir is accommodated in heating communication with theheating element. The heating element may be located such that heat maybe communicated to the reservoir and the heat may heat the fluid withinthe reservoir to a desired temperature. In some embodiments, the heatingapparatus may be designed to heat the fluid at a desired rate. Thus, insome embodiments, there may be additional features on the heatingapparatus to control the rate of heating of the fluid.

In some embodiments, the fluid may be heated to room temperature. Inother embodiments, the fluid may be heated to less than room temperatureand in still other embodiments; the fluid may be heated to above roomtemperature. In some embodiments, the heating apparatus may heat thefluid according to one or more preprogrammed profiles. The one or moreprofiles may be designed for various situations and/or various types offluids. Depending on the desired temperature, the heating apparatus maybe designed accordingly.

Thus, in various embodiments, use of an embodiment of the heatingapparatus may act to accomplish at least, but not limited to, one ormore of the following: decrease, minimize and/or eliminate downstreameffects of out-gassing; decrease, minimize and/or eliminate thesubjective amount of out-gassing such that the amount of out-gassing iscontrolled and/or predictable and therefore may be mitigated throughother means; decrease, minimize and/or eliminate and/or lessen theoccurrence of out-gassing; stabilize the temperature of the fluid tominimize potential effects of the temperature increase between, forexample, refrigerated temperature and room temperature; decrease,minimize and/or eliminate and/or lesson the effects of out-gassing inthe reservoir, including but not limited to, volume changes in thereservoir.

During the heating, the fluid may out-gas. Thus, following heating, thereservoir may be removed from the heating apparatus and air may bepushed out of the syringe/reservoir through, for example, but notlimited to, a filling needle 710, prior to loading the reservoir 704into the infusion pump. Thus, the heating apparatus may minimize and/oreliminate thermally produced fluid delivery errors.

In some embodiments, degassing of the fluid may be accomplished prior toloading fluid into a reservoir or prior to loading a filled reservoirinto an infusion pump by subjecting the fluid to a partial vacuum. Thismay be accomplished through a number of embodiments, including, but notlimited to, the following.

In some embodiments, once fluid is filled into the reservoir, he fillingneedle may then be removed from the reservoir and the reservoir may becapped with a cap that does not allow the movement of fluid in or out ofthe reservoir. The plunger may be pulled back to apply a vacuum to thefluid within the reservoir. Out-gassing may occur. Released air may thenbe pushed out of the reservoir prior to loading into an infusion pump.

In some embodiments, following filling of the reservoir, the reservoirmay be placed into a device or other where the reservoir is put under apartial vacuum. The fluid may out-gas. Next, the reservoir may be loadedinto the infusion pump.

In some embodiments, in addition to heating to out-gas, a system mayalso combine a vacuum with an elevated temperature/heating element,which may result in heating the fluid to a higher temperature. In someembodiments, the temperature increase may be minimized when appliedtogether with a vacuum. Additionally, the vacuum applied may beminimized when applied together with a temperature increase. Thus, insome embodiments, where the fluid is heated and a vacuum is applied tothe fluid, the temperature increase and/or the level of vacuum appliedmay be minimized. Thus, in some embodiments, it may be desirable toapply as low a vacuum as possible, thereby decreasing the amount ofturbulence and/or rate of flow through a heat exchanger and/orminimizing the contact area over a heat exchange surface, and thereforeminimize and or prevent extreme temperature and/or extreme pressurechange. This may be desirable for many reasons, including, but notlimited to, maintaining the viability of the fluid.

In some embodiments, while under pressure, the fluid may be removed froma vial into a reservoir and/or syringe or other, and once the desiredvolume of fluid has been loaded into the reservoir/syringe or other, thefluid path between the reservoir/syringe and the vial may be closed andthe syringe plunger may continue to be pulled back, i.e., applying avacuum onto the fluid. Following, the syringe or other may be vibratedand/or shocked and/or a force may be provided at a predetermined pointfor a predetermined time, i.e., a force pulse. This may enhance/amplifyair bubble formation i.e., fluid de-gas, and thus, in some embodiments,following vibration/force application, the air/gas may be pressed out ofthe reservoir/syringe.

In some embodiments, an automated filling device may be used which mayconnect a reservoir/syringe to a vial of fluid by a fluid line which, insome embodiments, may be a filling needle. In some embodiments, thedevice may automate the filling of the reservoir/syringe. Following, insome embodiments, the device may close/occlude the fluid line andprovide the vibration and/or force to the reservoir/syringe (i.e.,pulling a vacuum into the reservoir/syringe). In some embodiments, thismethod may be completed more than once, e.g., 2 or more times and/oruntil, in some embodiments, based on the volume of fluid in thereservoir/syringe and the amount of air extracted on any given attempt,the device may determine whether a threshold volume of air has beenremoved from the fluid, i.e., there may be a predetermined thresholdgoal amount of air to be extracted. In some embodiments a syringe havinga volume, for example, of 1.5-5 cc, may be used and filled to half or aportion of the volume, followed by a vacuum being applied. In someembodiments, the device may include a camera and/or other sensor todetermine the volume of fluid before and after air extraction/de-gas todetermine if the threshold goal has been met. In some embodiments, thedevice may communicate with the controller for the infusion pump and/orthe pump to input the amount of fluid in the reservoir prior to thereservoir being loaded into the infusion pump. In some embodiments, thissystem may be beneficial for many reasons, including but not limited to,improving air mitigation and increasing the accuracy of the volume offluid filled into a syringe/reservoir. In some embodiments, theabove-described system and method may include an optical sensor or othersensor to determine the plunger's displacement.

In some embodiments, the automated filling device may measure thetemperature of the fluid and this may be input into a control system 728that determines the amount of effort that is exerted onto the filledreservoir/syringe, i.e., how much force is applied onto the syringe toextract the air. For example, in colder temperatures it may be moredifficult to remove the air and therefore, may require more or longerapplication of vacuum and/or more or longer application of vibrationand/or force or both. In some embodiments, the temperature of the fluidmay be input into a control system 728 and the amount of heating of thefluid may be determined using the temperature readings. In someembodiments, the temperature readings may be used to determine both theamount of force applies to the syringe and the amount of heating appliedto the fluid.

In some embodiments, to minimize the vacuum applied to thereservoir/syringe, for example, where it may be desirable to protect thefluid, the device, in some embodiments, may measure the force (e.g., mayinclude a pressure sensor) being pulled on the syringe to correlate theforce with the pressure being exerted onto the fluid and therefore, itmay be determined when the vacuum has been depleted such that the vacuumno longer is working. Thus, the force or pull on the reservoir/syringemay be an output to determine when to stop/cease the force or pull andalso, to determine when a sufficient amount of air has likely beenpulled from the fluid, based on the force.

In some embodiments, using an optical sensor, for example, an opticaldisplacement sensor, to determine the displacement of the plunger,together with the pressure sensor to determine the pressure beingexerted onto the fluid, the control system 728 may calculate the volumeof air removed as well as correlate pressure with displacement.

Referring now to FIG. 12 one embodiment of a system for maintaining alower positive pressure within a fluid vial 702 is shown. It may bedesirable to maintain the fluid which will eventually be used in areservoir at or near atmospheric pressure rather than at a pressurewhich may result in a greater volume of dissolved gas in the fluid.Thus, in some embodiments, maintaining the fluid at or near atmosphericpressure may minimize post reservoir fill fluid out-gassing as theamount/volume of dissolved gas in the fluid is limited compared toembodiments where the pressure inside the vial is higher or increases.As shown in the FIG. 12, in some embodiments, a needle 716 is insertedthrough the septum 718 of the vial 702. The needle 716 may include twoends which are each open to the atmosphere. However, in someembodiments, the end exposed to the outside of the vial 702 may includea filter, which, in some embodiments, may be a hydrophobic filter (notshown), to maintain sterility and/or to maintain the needle as dry.

In some embodiments, the needle 716 may include a one-way check valve720 on one end of the needle 716. In some embodiments, the one-way checkvalve 720 may have a 1 or 2, for example, PSI cracking pressure. Whenthe pressure within the vial 702 is high enough, the vial 702 will vent.This may lower the positive pressure in the vial. In some embodiments,the check valve 720 may limit the internal vial 702 pressure so that itis no greater than atmospheric pressure plus 1 or 2, for example,additional PSI. Thus, in these embodiments, the apparatus/system shownin FIG. 12 may be beneficial for many reasons, including, but notlimited to, limiting the pressure due to atmospheric pressure change.

Referring now also to FIG. 13, in some embodiments, the device/systemshown in FIG. 12 may additionally include a vial manager apparatus 722that may be sized and shaped to accommodate the vial 702 such that thevial manager apparatus 722 may be removably attached to the vial 702. Insome embodiments, the vial manager apparatus 722 may include a pump 724,which may also be termed an air pump, in fluid connection with theinside of the vial 702 through a needle 716. The pump may be used forpumping air out of the vial 702, which may be, in some embodiments, anelectromechanical pump and/or a pump that may be manually operated. Thepump 724 may be used to apply a low vacuum on the inside of the vial702. In some embodiments, the pump 724 may be a diaphragm pump that maybe battery operated and works to pull, e.g., a PSI less than atmosphericpressure, which, in various embodiments, may include pulling at PSI fromless than 1 to 12, for example, vacuum on the inside of the vial 702.

In some embodiments, the vial manager apparatus 722 may include a powersource, i.e., a battery 726, to provide power to at least the pumpand/or the processor. In some embodiments, the vial manager apparatus722 may additionally include a processor 726 and/or a timer that may bepreprogrammed to turn the pump 724 on and off to limit the vacuum, e.g.,the pump 724 may pump for 30 seconds every 5 minutes. However, in someembodiments, the duration that the pump is on and/or the frequency ofthe durations may depend on the leak rate of the vial 702. In someembodiments, the pump 724 may run constantly.

In some embodiments, the vial manager apparatus 722 may additionallyinclude a pressure sensor (not shown) located within the path of theneedle 716. In various embodiments, the pressure sensor maycommunication with the processor/control system 728 and the pump 724 maybe activated based on the pressure data from the pressure sensor. Insome embodiments, where a pressure sensor is included in the needle 716,the device may determine if the vial 702 has tipped using the pressuresensor reading. In some embodiments, where a tip is determined, the vialmanager apparatus 722 may alarm using any type of alarm including butnot limited to, blinking or one or more lights, audio alarm and/orvibratory alarm. Determining when the vial 702 has tipped may bebeneficial for many reasons, including but not limited to, once the vial702 has tipped, the air pump 724 may not be able to pump air since fluidmay be in contact with the needle 716. Thus, the vial manager apparatus722 may not be able to pull a vacuum on the vial 702. Thus, it may bedesirable to alarm/alert once the vial 702 has tipped. This alarm/alertmay, in some embodiments, be triggered by the pressure sensor.

In some embodiments, the vial manager apparatus 722 may include one ormore lights to indicate conditions, for example, one or more greenlights and one or more red lights, indicating the status of the vialmanager apparatus 722 and/or the vial 702. In some embodiments, the vialmanager apparatus 722 may include one light which may, by, e.g.,blinking, indicate various status conditions.

In some embodiments, the vial manager apparatus 722 may include at leastone accelerometer that may be connected to a processor 728. This may beused to determine when/if the vial has tipped while in storage. In someembodiments, the vial manager apparatus 722 may additionally include atleast one alarm (for example, vibratory and/or audio and/or visual) toalert the user/care giver that the device has tipped. In someembodiments, the needle 716 may include a filter, which, in someembodiments, may be a hydrophobic filter (not shown). The hydrophobicfilter may be beneficial for many reasons, including, but not limitedto, protecting the air pump 724 from pumping fluid

In some embodiments, the vial manager apparatus 722 processor 728 mayinclude a vial manager control system. The system may include at leastone temperature sensor which may be located inside the vial managerapparatus 722 and may be in communication with the processor 728. The atleast one temperature sensor may provide temperature data on apredetermined frequency, e.g., every 5 minutes, and at a threshold highor low temperature reading, the apparatus 702 may alarm/alert. In someembodiments, the vial manager apparatus 722 may include a time keeperwhich, when, for example, the vial manager apparatus 722 is connected toa vial 702, the timer may be initiated, and at a predetermined time,e.g., 28 days, the vial manager apparatus 722 may alarm/alert the userthat the vial should be replaced and/or has been in use for thepredetermined amount of time. This may be beneficial for many reasons,including, but not limited to, alerting the user when the fluid insidethe vial 702 may be passed the expiration date thereby ensuring the userdoes not use expired fluid and/or medication for therapy.

The vial manager apparatus 722, in some embodiments, may be made fromany material, including, but not limited to, any type of plastic and/ormetal. In some embodiments, the vial manager apparatus 722 is placedover the top of the vial 702 and once the needle 716 pierces the septum718, the timer may initiate a countdown. Thus, the vial managerapparatus 722 provides a system for maintaining the pressure in a vial702 and also, for ensuring providing a method for determining when thevial 702 was first used, i.e., when the needle 716 is first insertedinto the vial 702. In some embodiments, the vial manager apparatus 722may be used while a vial 702 is “in use”, e.g., while a user is usingthe vial 702 for therapy.

In some embodiments, the vial manager apparatus 722 may include adisposable portion and a reusable portion. For example, in someembodiments, the portion of the vial manager apparatus 722 that connectswith the vial 702, including the needle 716, may be contained in thedisposable portion. Thus, the reusable portion may include, but is notlimited to, the processor, power source, and pump, etc. This may bebeneficial for many reasons, including, but not limited to, reusabilityof many elements of the vial manager apparatus 722.

In some embodiments; a stick-on pressure and/or force gauge may beplaced on a vial of fluid, and in some embodiments, on a vial ofinsulin. The gauge may tell the user the current pressure of the vial.In some embodiments, the pressure may be indicated as various colorshades. Any stick-on pressure gauge may be used including anon-reversible pressure label. In some embodiments, a ReversiblePressure Label may be used or a label with both reversible andnon-reversible components may be used.

In some embodiments, a pressure and/or force label may be included onthe vial. It may be desirable to include a pressure and/or force labelfor many reasons, including, but not limited to, determining whether apressure/force was exerted onto the vial that may be indicative of anelevated volume of air saturation in the fluid, i.e, may indicate thatthere may have been an increase in the volume of dissolved air in thefluid which may lead to additional out-gassing of the air. This may, insome embodiments, be indicative that the vial of fluid may becompromised and therefore, it may be desirable for a user/caregiver toknow whether the vial has been compromised.

In various infusion device, for example, including those shown anddescribed herein as well as in U.S. Pat. No. 7,498,563, issued Mar. 3,2009 and entitled Optical Displacement Sensor for Infusion Devices; U.S.Pat. No. 7,306,578, issued Dec. 11, 2007 and entitled Loading Mechanismfor Infusion Pump; PCT Application Serial No. PCT/US2009/060158, filedOct. 9, 2009 and entitled Infusion Pump Assembly, now Publication No. WO2010/042814, published Apr. 15, 2010; U.S. patent application Ser. No.11/704,899, filed Feb. 9, 2007 and entitled Fluid Delivery Systems andMethods, now U.S. Publication No. US-2007-0228071-A1 published Oct. 4,2007; U.S. patent application Ser. No. 12/347,985, filed Dec. 31, 2008and entitled Infusion Pump Assembly, now U.S. Publication No.US-2009-0299277-A1 published Dec. 3, 2009; and U.S. patent applicationSer. No. 12/560,106 filed Sep. 15, 2009 and entitled Systems and Methodsfor Fluid Delivery, now U.S. Publication No. US-2010-0185142-A1,published Jul. 22, 2010, which are all hereby incorporated herein byreference in their entireties, in some embodiments, thedisposable/reservoir portion of the infusion pump may include one ormore coatings to mitigate air bubbles. The coatings may be applied tothe fluid pathways within the disposable/reservoir portion and/or to theoutside of the reservoir. With respect to coatings applied to the fluidpathways, in some embodiments, a coating may be applied to change thesurface tension properties such that the surface is more hydrophilic.Increasing the hydrophilic properties of the fluid path may alter theangle of contact between an air bubble and the fluid path surface, thusenabling mitigation of the air bubble by priming or pumping. In someembodiments, the coating may be applied to the hard plastic portionand/or the membrane portion.

With respect to the reservoir, in some embodiments, a coating may beapplied to the outside of the reservoir. The coating may be selected todecrease the permeability of the reservoir thus, may decrease theincidence of air permeating the reservoir and therefore, may minimizeand/or decrease and/or lessen the incidence the air bubbles in thereservoir. As the coating may be applied to the outside of thereservoir, the coating used may be anything desired and is not limitedto fluid compatible materials. In some embodiments, the coating mayinclude, but is not limited to, one or more of the following: paryleneand/or oil. In some embodiments, the reservoir may be coated on theoutside and the coating may prevent air diffusion inward and water vapordiffusion outward. In some embodiments, the inside of the reservoir maybe coated with a material, including, but not limited to, a paryleneand/or oil and/or a hydrophilic coating material made by SurModics, Inc.of Eden Prairie, Minn., U.S.A., or other hydrophilic coatings that maybe compatible with the fluid in the reservoir. In some embodiments, thismay be desirable to allow for air to move through the reservoirmaterial.

Altimeter

Referring now to the various embodiments of infusion pumps includingthose described in U.S. Pat. No. 7,498,563, issued Mar. 3, 2009 andentitled Optical Displacement Sensor for Infusion Devices; U.S. Pat. No.7,306,578, issued Dec. 11, 2007 and entitled Loading Mechanism forInfusion Pump; and PCT Application Serial No. PCT/US2009/060158, filedOct. 9, 2009 and entitled Infusion Pump Assembly, now Publication No. WO2010/042814, published Apr. 15, 2010, and those infusion pumps known inthe art, in some embodiments, an altimeter may be introduced to theinfusion pump.

Referring to U.S. patent application Ser. No. 11/704,899, filed Feb. 9,2007 and entitled Fluid Delivery Systems and Methods, now U.S.Publication No. US-2007-0228071-A1 published Oct. 4, 2007; and U.S.patent application Ser. No. 12/347,985, filed Dec. 31, 2008 and entitledInfusion Pump Assembly, now U.S. Publication No. US-2009-0299277-A1published Dec. 3, 2009, which are both hereby incorporated herein byreference in their entireties, in some embodiments, the altimeter may beused in Acoustic Volume Measurements, for example, for changing thedampening based on ambient pressure. Still referring to U.S. patentapplication Ser. No. 11/704,899, filed Feb. 9, 2007 and entitled FluidDelivery Systems and Methods, now U.S. Publication No.US-2007-0228071-A1 published Oct. 4, 2007; and U.S. patent applicationSer. No. 12/347,985, filed Dec. 31, 2008 and entitled Infusion PumpAssembly, now U.S. Publication No. US-2009-0299277-A1 published Dec. 3,2009, in some embodiments, the disposable/reservoir portion of theinfusion pump may include an intravenous needle connected to the tubing,rather than an infusion set, as discussed in various embodiments. Thus,in some embodiments, the infusion pump may be used to administerintravenously and is not limited to subcutaneous infusion. In some ofthese embodiments, the fluids infused may be those used to minimizebleeding, for example, but not limited to, morphine and/or bloodpressure lowering medications and/or other similar therapeutics.

Cannula Detection

In some embodiments of some infusion pumps, the cannula may be insertedinto the user such that the cannula may be located directly between theuser's skin and the infusion pump. This presents some challengesincluding, but not limited to, determining when the cannula has becomedislodged and determining an occlusion in the cannula.

In some embodiments, two electrode contracts may be used. One electrodecontact may be in located between the infusion pump and the user's skinand is in contact with the user's skin, the other that is in electricalcontact with the infusion pump. An electrical path between the twoelectrodes is established. Using high impedance/low voltage, theimpendence between the two electrodes is determined and tracked. If theimpedance reaches a very high value, for example, “infinity”, anocclusion and/or cannula dislodgement may be inferred. The user may bealerted. This may be desirable because if there is cannula dislodgement,the user is no longer receiving their fluid therapy. In the case of aninsulin pump, the user may experience an hyperglycemic event. Earlydetection and alerting of the user may increase the safety of thesetypes of infusion pumps.

While the principles of the invention have been described herein, it isto be understood by those skilled in the art that this description ismade only by way of example and not as a limitation as to the scope ofthe invention. Other embodiments are contemplated within the scope ofthe present invention in addition to the exemplary embodiments shown anddescribed herein. Modifications and substitutions by one of ordinaryskill in the art are considered to be within the scope of the presentinvention.

What is claimed is:
 1. A system comprising: a fill adapter device comprising: a housing comprising a housing septum and a vial input, wherein the vial input is configured to attach to a vial comprising a vial septum; and a heat exchanger located inside the housing comprising: a heating element; and a fluid pathway, the fluid pathway fluidly connected to the vial septum and the housing septum, whereby fluid enters the heat exchanger through the vial septum and flows through the fluid pathway and whereby the fluid is heated by the heating element; a reservoir including a plunger and a plunger rod; and a filling needle configured to be removably attached to the reservoir; wherein fluid from the vial flows through the fluid pathway and fluid from the vial is first heated and then loaded into the reservoir through the filling needle.
 2. The fill adapter of claim 1 further comprising a pump to pump fluid into the fluid pathway at a predetermined rate.
 3. The fill adapter of claim 1 further comprising a processor for controlling the heating of the fluid according to one or more preprogrammed profiles.
 4. A fill adapter device comprising: a housing comprising a housing septum and a vial input, wherein the vial input is configured to attach to a vial comprising a vial septum; and a heat exchanger located inside the housing comprising: a heating element; and a fluid pathway, the fluid pathway fluidly connected to the vial septum and the housing septum, wherein fluid from the vial enters the heat exchanger through the filling needle input and flows through the fluid pathway and wherein the fluid from the vial is heated by the heating element while flowing through the fluid pathway.
 5. The fill adapter of claim 4 further comprising a pump to pump fluid into the fluid pathway at a predetermined rate.
 6. The fill adapter of claim 4 further comprising a processor for controlling the heating of the fluid according to one or more preprogrammed profiles.
 7. The fill adapter of claim 4 further comprising wherein the fill adapter is configured to be attached to a vial of fluid. 